LEED Minimum Program Requirement #6, requiring energy and water use reporting, is the most controversial and the most difficult to comply with. Our free webcast explains it step by step.

Free Webcast: LEED Energy Reporting Made Easy: Fulfilling LEED-2009 MPR #6

Tues. Feb. 28 | 1 p.m. Eastern Time

When the Minimum Program Requirements (MPRs) were introduced in 2009, it quickly became clear that MPR #6 would be perhaps the most controversial and the most difficult to comply with. Under the requirements of MPR #6, certified LEED-2009 projects are committed to sharing whole-building energy and water usage data.

Many projects have had questions about how to comply (and if they really have to!), and USGBC has taken time to build out its support for this requirement. Now, the support is there, and LEEDuser is here to help answer your questions--and make MPR #6 easy with this free webcast--register now!

USGBC's MPR #6 expert answers your questions

LEEDuser is pleased to offer this presentation by Lauren Riggs, manager of LEED performance at USGBC. This live, half-hour webcast will cover the following topics:

• The three options for BD&C projects to comply with MPR #6, including through use of Energy Star or LEED-EBOM
• The two options for LEED-CI projects to comply
• Tools under development to support performance tracking in LEED project certification
• The role of the MPRs in achieving LEED certification--or not
• Connections to EAc5: Measurement & Verification
• The Building Performance Partnership (BPP) and its role in MPR #6 compliance

MPR #6 Frequently Asked Questions

The webcast will cover some of the common problems that project teams face in earning MPR #6, among them:

• Can I get an exemption?
• How will USGBC use our data?
• Will my project be decertified if it performs poorly?
• My project is outside the U.S. Can I use Portfolio Manager?
• How often should I record energy and water data?
• When do I have to start reporting data?

Lauren shares specific to-do's, case studies, and tips you can use to make this entire process easier for your project team.

Also, bring your MPR #6 questions to the webcast for a Q&A session with Lauren!

Continuing education

LEEDuser will offer 0.5 CE hours for AIA and LEED AP credential maintenance, to anyone attending the entire webcast. (Please stay to the end for instructions on logging those hours!)

About the presenters

Lauren Riggs – USGBC
Lauren Riggs, Manager of LEED Performance at USGBC is responsible for the management of the building performance programs central to LEED. These programs include Building Performance Partnership, Portfolio Partners Program and LEED Recertification.  Additionally, Lauren developed and maintains the LEED Online Minimum Program Requirement #6 documentation requirements. Her work emphasizes the imperative linkages between the existing buildings certification process and requirements and ongoing tracking of building performance.

Tristan Roberts – LEEDuser
The webinar will be moderated by Tristan Roberts, editor of LEEDuser.com, a website that provides how-to resources for LEED certification teams. Tristan is also Editorial Director for BuildingGreen, publishers of LEEDuser as well as Environmental Building News and GreenSpec.

The Army is still going for Gold and Platinum despite recent legislation calling a halt to LEED spending.

The federal government has been one of the biggest supporters of LEED certification in the last few years, with the General Services Administration (GSA) requiring basic LEED certification for all federal buildings starting in 2003 and then upping that requirement to LEED Gold in 2010.

The military has been on the cutting edge of green building from the beginning. The Navy adopted sustainable design principles before LEED even existed, as we reported way back in 1998. The Army embraced LEED in 2006 and recently began the much more radical work of moving all its installations to net-zero energy, water, and waste. As Katherine Hammack, assistant secretary of the Army for installations, energy, and the environment, put it to EBN earlier this year, "Energy security is mission critical."

It doesn't cost more

We feared that might all change when we saw that the most recent military appropriations legislation requires explicit justification for any spending on LEED above the Silver level. What's worse, this decision pretends to be about money but appears to have been made over certified wood credits. (Watch this space for in-depth coverage of the "wood wars" in coming weeks.)

Hammack is having none of it. In a call with reporters yesterday, she reiterated the Army's commitment to net-zero and LEED and gave an update about some of the progress that's already been made. "We're finding it does not cost more to design and construct to LEED" standards, Hammack said.

On the warpath for LEED

Will the Army then be submitting cost-benefit analyses for each project, as the legislation seems to require? Hammack said no.

"The challenge right now is one of education," she explained. "If a building got a Gold-level certification and we were striving for Silver, that does not mean there was an incremental cost. We're working to help prepare a report for Congress so they understand the benefit of high-performance buildings."

Hammack clearly views these benefits as, at least in part, financial.

Can they do this?

The legislation in question does have a loophole for LEED Gold and Platinum projects as long as they don't cost more. As we reported at the time, "Exceptions may also be made without a special waiver if achieving Gold or Platinum 'imposes no additional cost'."

That loophole is big enough to blithely drive a tank through without bothering to show ID at the checkpoint. You apparently don't have to prove that it didn't cost more--or the Army is interpreting it that way, at any rate, while working closely with Secretary of Defense Leon Panetta on "educating" Congress.

Build to the standard but don't certify?

Another reporter asked if you could bypass the requirements by building to LEED standards but not bothering with certification. Hammack wasn't warm to that idea.

"We like the LEED program because it gives another set of eyes on the construction details and helps guide the direction of architects and engineers," Hammack replied. "The cost of LEED certification is very minimal in comparison to the benefits of LEED certification and the recognition that the building has achieved certain goals."

Zero energy wasted on dithering

"With a limited amount of water, a limited amount of resources, and an increasing world population," Hammack said, "we need to improve our stewardship over the resources we have."

Most of the call with Hammack was devoted to the progress on net-zero pilot projects. She and the rest of the Army clearly are not wasting time on questions of whether to LEED or not to LEED.

Lighter, more fire-resistant, and a better insulator, autoclaved aerated concrete caught on in the rest of the world ages ago. It's taking a lot longer in the U.S.

To read what manufacturers and distributors say about it, you'd think autoclaved aerated concrete (AAC) was some kind of new, space-age environmental miracle.

Although it certainly has some nifty properties, AAC isn't new and isn't miraculous--but it's certainly popular in Europe, and has been for decades; according to one source, it accounted for 60% of all new construction in Germany in 2006. It has enjoyed pretty flat market share (of near zero) here in the U.S., though, since it was first introduced in the 1990s.

Is there space for AAC in the U.S. market? Should the green building community be working to make space?

How AAC is made

AAC is similar to other concrete types, except that it contains no aggregate; sand or fly ash is included, with aluminum powder added to react with one of these ingredients and "leaven" the concrete, creating tiny bubbles just like baking soda does when it reacts with the buttermilk in your muffin batter. (Your muffins are full of carbon dioxide bubbles, but AAC is full of hydrogen bubbles.)

[Note: Robert Riversong points out in comments that sand is aggregate, which I also thought when I started researching it, but after some more digging, my understanding is that the sand is used as a reactant and is therefore not considered aggregate in AAC. For more, see here.]

The concrete is poured into molds, left to rise, and then "baked" in an autoclave, which uses steam and pressure to complete the chemical reactions and speed up the curing process significantly--completing in hours rather than weeks. The resulting blocks are so full of bubbles that a block of the same size has about one-fifth the material required by regular concrete.

Like conventional concrete masonry units, AAC is sold in a variety of block shapes and sizes, but unlike conventional units, most don't have cores. They are porous and light, like muffins, but not hollow.

Benefits of AAC

The main advantage of AAC when it was first developed in Sweden in the early 20th century was simple: it wasn't wood. It's still not wood, but in North America (unlike in Sweden at the time and in most of Europe now), wood is still plentiful and cheap.

Compared with conventional concrete, AAC still has advantages, though:

• It uses less material--important for concrete, since portland cement is one of the most energy- and carbon-intensive building materials.
• Despite the energy-intensive autoclaving process, manufacturers say it takes about 50% less energy to make, because of the lower portland cement content by volume (we're haven't found anyone to challenge those claims, but are still looking for data).
• It's lighter, which cuts down on transportation costs and fuel use.
• It's a better insulator, with a steady-state R-value just a hair above R-1 as opposed to something more like R-0.2 (neither of these factors in thermal mass, which we'll get to later).
• Air leakage is minimal.
• AAC also has excellent soundproofing properties.
• It can also be used as a firebreak.

Drawbacks of AAC

In a report written for UC–Davis (PDF), Stefan Schnitzler finds few disadvantages to AAC. Here are the two demerits on his list:

• There are few manufacturers in the U.S. (that was in 2006, and now there are almost none, since Xella has moved its Hebel operation to Mexico); this means higher costs, which is a huge barrier for adoption.
• AAC requires a learning curve for builders, because the mortar application is more precise.

We would like to add a few drawbacks that we've found:

• The barriers for builders don't stop with the mortar. According to Derek Taylor, owner of AAC distributor SafeCrete, the only manufacturer in North America right now is a German company whose block dimensions don't work for U.S. builders. These often need to be sawed, adding labor and fuss to a building system that's supposed to be simple. (Taylor's looking forward to two new plants coming online in the States in the next couple years.)
• Since right now your AAC is most likely coming from Mexico, the advantages offered by lighter weight will diminish significantly as the mileage increases.
• Thermal properties are better than those of conventional concrete, but they aren't good enough to make AAC a viable wall material (relative to BuildingGreen-recommended R-values) in most U.S. and Canadian climates without additional insulation. (The European climate, where AAC is popular, is milder.)
• Unless rebar is added--which adds to the weight and amount of material in the blocks--AAC can only be used for low- and mid-rise construction. But it seems to be popular for single-family homes as well as schools.
• Unlike conventional concrete, AAC can't be used as a finish; it is more porous and needs cladding or stucco on the outside so it won't absorb moisture.

Would you use AAC?

That said, AAC does appear to have significant advantages for applications where conventional concrete would normally be the best material--like in the American Southwest and in other climates where thermal mass can increase the "effective" or "mass-enhanced" R-value of the wall. Even then, its performance may still be outmatched by that of insulated concrete forms, depending on the needs of the client.

Unfortunately, much of the information we have on AAC performance in the U.S. comes from manufacturers. We'd like to hear some empirical evidence from the field.

Are you using AAC on any of your projects?

If you've used it, how did it perform? If not, what would it take for you to try it out?

Periodic drought is something that a significant portion of the U.S. will have to get used to in the coming decades. Climate scientists tell us that while precipitation will increase overall with climate change, certain regions, including the American West, will see increased frequency of drought.

I certainly saw that last year, when I spent six weeks bicycling through the Southwest, from San Diego to Houston. Most of the 1,900 miles I covered had seen barely a drop of rain since the previous fall. Statewide, Texas had an average of just 15 inches of rain in 2011--barely half of the typical rainfall.

Ironically, drought sometimes exacerbates water shortages in other ways. Wildfires in Lubbock, Texas last June knocked out 20% of the city's crucial water wells, reducing the city's water supply by nine million gallons per day for two weeks. Then in July, shrinking clay soils in Fort Worth, Texas resulted in more than 200 breaks in water mains, spilling precious water into the ground. Austin suffered similar problems as did other communities throughout the state that was suffering from the worst drought on record. As we think of adaptation to climate change and resilience, dealing with water has to be a part of our focus. In this blog I'll cover how to improve the efficiency with which we use water and measures to ensuring access to water during shortages.

Use water efficiently

When water becomes scarce, it is all the more important to use that water efficiently. During drought emergencies, restrictions in certain water uses (such as outdoor irrigation) are commonly instituted. By planning ahead and replacing water-intensive lawns with low-water-use native landscaping (often called "xeriscaping"), your grounds will likely do just fine without water.

If you want to be able to get by with stored water during interruptions in water supply (see below), you need to make that stored water go as far as possible. This means ultra-low-flush toilets, such as the new generation of high-efficiency toilets (HETs) that use no more than 1.28 gallons per flush or that offer two flush volumes, showerheads using as little as 1.5 gallons per minute, bathroom faucets with flow rates as low as 0.5 gallons per minute, water-conserving horizontal-axis (front-loading) clothes washers, and top-efficiency dishwashers.

One can go even further with water-efficiency using composting toilets that don't use any water, waterless urinals, and graywater systems that capture water from a lavatory sink to re-fill the toilet.

Relying on a spring on a hill

Rural homeowners with springs that gravity-feed water to the house are at a distinct advantage when it comes to resilience. Our home in Dummerston used to be served by a spring on the hill above our house that relied on gravity to deliver water to a cistern in our basement. The vertical drop from the spring wasn't enough to deliver a strong shower, so we had a shallow-well pump in the basement to charge a pressure tank, but during power outages I could turn a few valves and switch over to gravity-pressure for our home water system; the 20 psi of pressure provided a weak shower--but a lot better than none. Unfortunately, after several years of the spring running dry in August, we drilled a well and pretty-much abandoned the spring.

On-site water storage

If your water supply is interrupted for whatever reason, the only real option is to have stored water on-site. Rural homeowners who face periodic power interruptions are familiar with this issue. Unless we have back-up generators, when we lose power we lose our water, because our deep-well pumps don't work. This is my situation. We have a pressure tank in the basement, so we may still have a few gallons of available water after a power outage, but not much. It's always a good idea to have stored water on hand for emergency use.

Those five-gallon carboys used with drinking-water dispensers work well for storing potable water. Fill them, seal them to keep insects and dust out, and keep them in a dark location to prevent algae growth. Open containers may be fine for storing non-potable water that can be used to flush toilets. When we lose power, we shut off the fill-valve to one of our toilets, and fill it manually after flushing. You can carry water from a stream, collect water from your roof in buckets positioned under the eaves, or rely on a full-blown rainwater harvesting system (see below).

Rainwater harvesting

A greater level of resilience can be achieved with a rainwater harvesting system. The simplest of these systems is a rain barrel positioned under a downspout at the corner of your house. With larger systems, multiple downspouts feed rainwater into a large tank, or cistern, that stores the water. Many types of cisterns are available, made from plastic, fiberglass, galvanized steel, wood, or cement.

I've seen rainwater systems with buried cisterns that hold tens of thousands of gallons, but more common are tanks holding a few thousand gallons in an outdoor shed or basement. Being able to gravity-feed water from a cistern is an advantage, but that's often hard to do in cold climates, since the tank has to be kept from freezing.

Simple rainwater harvesting systems are typically used (during non-emergency times) for outdoor irrigation. More sophisticated systems are designed to provide potable water and include first-flush systems (to discard the first water that comes off a room during a rainstorm), filtration, and purification systems to ensure safe water. When used for potable water, a metal roof is usually the best surface, since less detritus is held in the roof surface.

About this series

Throughout this resilient design series, I'm covering how our homes and communities can continue to function in the event of extended power outages, interruptions in heating fuel, or shortages of water. Resilient design is a life-safety issue that is critical for the security and wellbeing of families in a future of climate uncertainty.

Alex is founder of BuildingGreen, Inc. and executive editor of Environmental Building News. To keep up with his latest articles and musings, you can sign up for his Twitter feed.

Will environmental product declarations end greenwashing for good? Not so fast.

This is Part 3 in our series on transparency.

Part 1: Why We Care About Product Transparency

Part 2: Why We Need "Nutrition Labels" for Building Products

We all want to know more about where our building products come from and what's in them. Finally, with the emergence of environmental product declarations, we're going to find out!

Aren't we?

The promise of the product transparency movement is huge, and we think this nascent trend is going to play a big role in sustainable manufacturing, design, construction, and operations in the next few years--one reason why we dedicated this month's EBN feature to product transparency.

But things aren't as simple as they might seem in this uncharted realm. There's more to environmental product declarations (EPDs) than meets the eye. And in many cases, there's less than meets the eye too. While many manufacturers are working hard to show leadership on true transparency, there is also a risk of insidious greenwashing like we've never seen before.

Five myths about environmental product declarations

• Products "earn" an EPD. Far from it. Manufacturers pay tens of thousands of dollars to get one, and the fact that a product has one tells you absolutely nothing about its environmental performance. You have to actually read the report to know whether the product is environmentally preferable or not.
• An EPD is like a nutrition label for building products. When's the last time you saw a 20-page nutrition label on your Cheerios? We're guilty of spreading this one ourselves, but it's not really true...at least not yet. Yes, the information in an EPD must follow a standard format, but that's where the similarly ends. For one thing, EPDs are completely voluntary--but also, we're very far from having an at-a-glance on-product label, although there are efforts to develop this. Here's one proposed by forward-thinking designers like Perkins + Will.
• EPDs are about science, not marketing. EPDs are backed by life-cycle assessment, and both have to be done by a third party in accordance with ISO standards. But companies can pick and choose which products they want to have EPDs for, and many will choose for marketing reasons; you won't find out how clean the company overall is by looking at one product's EPD. By contrast, InterfaceFLOR is working to develop EPDs for all its products--but Interface is definitely an exception. You may also find marketing language in some parts of the report.
• EPDs list all the ingredients in a product. Yes, the EPD has to list the materials the manufacturer uses--but you aren't likely to find out what's actually in those materials (like flame retardants or insecticides, for example) by looking at an EPD. We're working with the Healthy Building Network and a variety of manufacturers and other stakeholders to develop a health product declaration (HPD) that could help fill in the gaps. One of the things we're hoping the trend toward EPDs and HPDs will do is to help manufacturers get more information from their suppliers about potentially harmful ingredients.
• EPDs include information on toxicity and ecology. EPDs can sound a lot more comprehensive than they are. Although the life-cycle assessment behind the EPD will look at "human health" or "ecological" effects, those categories sound broader than their names justify. (See our recent coverage of a life-cycle assessment of hand-drying methods, where "ecosystem quality" was narrowly defined as "potentially disappeared fraction of plant species per square meter per year.") As far as human health goes, the HPD could help here too.

Where EPDs come from: the infographic

The success of product transparency depends on the design community knowing what an EPD is--and what it isn't.

In the process of writing the feature article, we put together an at-a-glance chart to explain where EPDs actually come from and to show a few key points you should know about them. Click above to view a larger version. Click here to download a PDF for printing.

Why we need EPDs, even though they're flawed

While you're printing it out, take five minutes to watch our fun video exploring what we think is so great about product transparency--including what you can do to make sure all the building product information you need is at your fingertips.

Contact with nature is not just an amenity: it's important for well-being. Green walls liven up urban spaces while improving building performance.

I live in Vermont, where agriculture is an integral part of our culture. I drive past the farms as the seasons change and see when the corn is high or when too much rain has made plowing impossible. And the family sees the results at the local farmer's market. Whenever I visit urban areas, I inevitably end up at the local park or waterfront for my early-morning runs.
I value this connection with the natural world--or biophilia--and maybe it's more than just a lifestyle choice. Biophilia has been shown to have tangible benefits, including reduced stress, improved productivity, and faster healing, to name a few, but integrating greenery among limited--and expensive--urban real estate is no easy task. Maybe the answer is to think vertically.

What is a green wall?

Exterior green walls, sometimes referred to as living walls, green facades, eco-walls, and a variety of other names, use frames mounted to exterior walls to support vegetation growth. Their greenery helps

• break up the urban landscape of concrete, glass, and steel;
• improve the thermal performance of a building by creating shade and an air space between the plants and the building;
• absorb carbon dioxide;
• mitigate stormwater runoff;
• and reduce heat and noise.

And since thermal performance and energy-saving design are not visible to the public, green walls are one way for building owners to advertise their green credentials.

GSky exterior Pro Wall System

But green walls have to be well designed and maintained or else you can end up with mold, moisture damage, or dead plants. GSky's exterior Pro Wall System reduces these risks using a stainless steel frame and panels that incorporate a structural growth medium. The plants are pre-grown to design specifications, monitored for temperature and moisture, and watered automatically using a drip irrigation system.
Designing the wall is no easy task. It begins with careful assessment of the site, water and drainage consideration, seismic and wind loads, and power and placement of the irrigation system. Local plants are then selected and pre-grown in a nursery before the panels are installed along with the frame, irrigation, and monitoring system.
The monitoring system is automated, setting off alerts if there is a problem with the irrigation, and can be paired with GSky's maintenance program. These green walls do not have to be a single shade of green, either. Using different plant species, you can create designs within the greenery.

More basic green walls

GSky also offers its Basic Wall Container System, which contains a trellis and integrated containers to support vine growth. The containers are three feet and five feet high, and the vines can be either pre-grown or allowed to grow naturally, which could take up to two years.
You can't get plant designs with these systems. They are meant for large exterior walls, and can even include a catwalk behind the façade of plants for easier maintenance on high walls. Like the Pro Wall System, they come with an irrigation and monitoring system.

Keeping the "green" in "green wall"

Providing the benefits of biophilia using a green wall only works if the plants are actually green. GSky ensures its systems perform with warranties of ten years on the planters, five years on the irrigation system, and a "100% Plant Health Guarantee" when paired with the maintenance contract.
We've updated our green walls section in GreenSpec and added a couple of new products. Check them out. While green walls might not be ideal for every building or climate, the more greenery we can add to urban environments, the more I'll feel at home while visiting.
 

House location and design are the starting points in achieving resilience--where the house located, how well it can weather storms and flooding, and how effectively it retains heat and utilizes passive solar for heating and daylighting. Beyond that, we should look to more active renewable energy systems for back-up heat, water heating, and electricity. This week we'll review these options.

Wood stoves

In rural areas, clean-burning wood stoves provide an easy option for back-up heat. With a compact, highly energy-efficient (resilient) home, a single, small wood stove can effectively heat the entire house when there is a power outage or interruption in heating fuel. Even in our current home, which is far from what I would call a "resilient" (relative to energy performance), we use a wood stove as our primary heat source--albeit accepting significantly cooler temperatures in parts of the house that are distant from the wood stove. Wood stoves are dirty, though--even EPA-compliant models (as all new wood stoves sold new today must be). In a rural area, such as where I live, reliance on wood heat may be acceptable, but in more densely populated areas extensive use of wood heat would cause significant pollution problems. Even in our area, when there is a power outage and more residents fire up their wood stoves, the air quality deteriorates. Thus, wood heating makes the most sense when the house to be heated is highly energy efficient so that little wood needs to be burned to maintain comfortable, safe conditions. And then, the wood stove should be operated for maximum combustion efficiency (minimum smoke production).

Pellet stoves

Like wood stoves, pellet stoves can do a good job of heating an energy-efficient house. Because of the fan-supplied combustion air, pellet stoves tend to be much cleaner-burning than wood stoves. The need for electricity to operate, though, makes pellet stoves inherently less resilient.

Our pellet stove--the sole heat for the apartment above our garage--works like most pellet stoves when AC electricity is available: electric coils ignite the pellets during start-up, a fan brings combustion air to the burn-pot in the stove, and another fan blows the heated air into the room. In the event of a power outage, however, our pellet stove--unlike most--can still be operated. The fans in our Quadra-Fire Mt. Vernon AE have DC motors, and we have jumper cables that allow us to operate the stove during a power outage by clipping them to an automotive or other deep-cycle 12-volt battery. This back-up power isn't enough to start the pellet stove (we have to do that manually with pellet starter gel or some kindling), but the battery can power the two fans.

Solar electricity

The ultimate in resilience can be achieved with a solar-electric (photovoltaic) power system that can be used when the grid is down. Photovoltaic (PV) systems directly convert sunlight into electricity. PV modules can be installed on a roof or on ground-mounted racks. Most use silicon wafers that are specially made so that photons of light excite electrons and generate direct current (DC) electricity. An inverter in most PV systems then converts that DC electricity into alternating current (AC) that can be used by standard household appliances and also fed into the utility grid through a net-metering system.

The problem with most grid-connected PV systems is that when the grid goes down (during a power outage), you can't use the electricity. This is a safety feature with grid-connected PV systems to prevent them from feeding electricity into the power grid when linemen may be repairing down wires. To serve as a power source during a power outage (key to resilience), it is generally necessary to install some battery back-up and a "hybrid" PV system. These systems are more complex (and costly), because they include not only a battery bank, but also controls that send power either to the battery bank or power grid, depending on the charge state of the batteries and status of the grid. There are apparently some specialized inverters that allow electricity to be used in the home (during the daytime when the PV system is producing electricity) even when the system is disconnected from the grid during an outage, but these inverters are uncommon.

Solar water heating

To heat water when the electric grid is down the best option is a solar water heating system that can operate without AC electricity. Some "active" solar water heaters have DC pumps with integral PV modules that operate the pump when the sun is shining--thus the PV module serves both as the controller and the pumping power. There are also two types of passive solar water heaters that require no electricity. Thermosiphoning systems have the solar collector mounted below the storage tank, and solar-heated water rises through natural convection into the storage tank when the sun is shining. With batch or integral-collector-storage (ICS) solar water heaters, the water is stored right where it is heated (with water pressure delivering that water to a collector on the collector on the roof).

A solar water heating system can be augmented with water heating coils in a wood stove to ensure adequate hot water during the winter months when there is less solar energy.

About this series

Throughout this resilient design series, I'm covering how our homes and communities can continue to function in the event of extended power outages, interruptions in heating fuel, or shortages of water. Resilient design is a life-safety issue that is critical for the security and wellbeing of families in a future of climate uncertainty.

Alex is founder of BuildingGreen, Inc. and executive editor of Environmental Building News. To keep up with his latest articles and musings, you can sign up for his Twitter feed.

There are more than 20 different standardized tests manufacturers can invoke to "qualify" as a code-accepted weather-resistive barrier (WRB); with our GreenSpec section on WRBs, we've picked just one that we think does the job.

It's not easy being a weather-resistive barrier (WRB): it has to stop liquid water, be tough and not tear, but also be flexible to wrap around building elements. And it often needs to be vapor-permeable to promote drying.

Finally, water-tight standards

In the past, manufacturers could cherry-pick the standardized test to use to "qualify." That's how we ended up with industry acceptance of perforated and cross-woven housewrap that literally leaks like a sieve.

Now we have a new ASTM "Standard Specification for Vapor Permeable Flexible Sheet Water-Resistive Barriers Intended for Mechanical Attachment." This standard also aligns with the latest version of the ICC-ES Acceptable Criteria (AC) 38–"Acceptance Criteria for Water-Resistive Barriers (PDF)." The table below presents the requirements for WRBs used in the new standard and now by GreenSpec.

Here are the key points from the table.

1. Two types of WRBs: Type I WRBs have what is described as a "base" level of water resistance. Type II WRBs have what is described as an "enhanced" level of water resistance. This difference is reflected only in the water-resistance requirements. GreenSpec requires Type II compliance.
2. Tensile strength or breaking force: There are three different ASTM test methods from which to choose; all evaluate the strength of the material.
3. Vapor permeability: All WRBs must be a minimum of 5 perms, considered to be vapor semi-permeable (Joe Lstiburek, Ph.D., P.E., of Building Science Corporation classifies materials in the range of 1 to 10 perms as Class III vapor retarders, based in part on the Canadian General Standards Board approach). This is ideal because WRBs should keep water out but also allow drying.
4. Pliability: The pliability test ensures WRBs are pliable even when they are cold (32?F).
5. Aged testing: The tests for tensile strength and water resistance must be conducted for materials "as received" and "aged." Aged testing involves cycles of wetting and drying as well as ultraviolet (UV) light exposure.

Find out if your favorite housewrap qualifies

Most high-quality, well-known spun-bonded polyolefin housewraps (such as Tyvek and Typar) comply with the new ASTM standard Type II requirements; the same is true for quality building papers (Fortifiber, for example).

You might not find explicit compliance to this new standard on a manufacturer's website; if it's not clear, ask them. Or just use a building paper or housewrap listed in GreenSpec.

You still have to install it right!

Does this new standard solve all of our building-assembly problems? Not by a long shot; you still need to marry the WRB to all flashing details at penetrations and transitions. But it sure makes a lot of sense to start with the right materials as you design, spec, and build high-performance building assemblies.

What are your experiences with WRBs, and questions? Please post your comments below.

Over the past month-and-a-half, I've been focusing on resilient design--which will become all the more important in this age of climate change. Achieving resilience in homes not only involves keeping them comfortable in the winter months through lots of insulation and some passive solar gain (which I've covered in the previous two blogs), it also involves keeping them from getting too hot in the summer months if we lose power and our air conditioning systems stop working. This week, despite the freezing weather, we'll look at cooling-load-avoidance strategies and natural ventilation.

Orientation and building geometry

With new houses, we can relatively easily control orientation and geometrical form to minimize unwanted solar gain. The optimal orientation for a house is with the long axis running east-west, so that the longer walls face south and north. This allows the house to benefit from the sun when we want that heat, but keep it out when we don't want it. The sun always rises in the east and sets in the west, but in the summer it rises much higher in the sky. By having more windows facing south, most of the sunlight will glance off that glass during the summer when the sun high overhead, while in the winter, with the lower-angle sunlight, most of that sunlight shines through those windows--providing passive solar heating (see last week's blog). At the same time, having fewer windows on the east and west make sense relative to summertime overheating. Significantly more sunlight shines through a square foot of east- or west-facing window during the course of a day in the summer than through a square foot of south- or north-facing window, so limiting east and west windows helps to prevent overheating.

Window selection

The type of glazing in our windows has a major impact on how much sunlight is transmitted through them. This is why it almost always makes sense in well-insulated buildings to "tune" the windows by orientation. By this, I mean using glass (glazing) on the south that transmits a high percentage of the sunlight striking it and glass on the east and west that transmits less sunlight. We refer to this property as the solar heat gain coefficient (SHGC); it is the fraction of total solar energy transmitted through the glass (assuming the sunlight strikes the glass at a normal (perpendicular) angle.

A good rule-of-thumb is to select south-facing windows that have SHGC values of 0.6 or higher (0.5 or higher with triple-glazed windows), and east- and west-facing windows with SHGC values of 0.3 or lower. Windows with SHGC values of 0.6 will transmit twice as much solar energy as windows with SHGC values of 0.3. The beauty of recent advances in glazings it that we can now have fairly large window areas (to provide views and natural lighting) without nearly the energy penalty (both from heat loss and unwanted solar gain) we had two or three decades ago.

Shading windows from direct sun

On the south, we can also use simple overhangs or awnings to block virtually all of the direct sun. On the east and west, different shading strategies are better, because the sun is lower in the sky. For these windows, exterior shade screens or roller blinds can be very effective. So can plantings of tall annuals like hollyhocks or vines like clematis, morning glory, and grape.

Designers and builders in the south learned the principles of shading windows long ago. Traditional architecture in hot climates often included wrap-around porches that kept direct sun out of the house, while providing pleasant outdoor living space. (Part of resilient design is looking at how our grandparents or great grandparents built--and returning to some of this vernacular architecture that is so well-adapted to the local climate.)

Reflective roofs and walls

Light-colored roofs and walls reflect, rather than absorb, most of the sunlight striking them. By not heating up as much, less heat is transmitted through to the interior. With high insulation levels in roofs and walls (see below), the need for reflective exterior surfaces is less important, but this strategy can still make a difference.

High insulation levels and tight construction

Just as an energy-efficient building envelope reduces heat loss in the winter, it also reduces unwanted heat gain during the summer--thus helping to control cooling loads and maintain comfort. If we follow the sort of recommendations for insulation levels for resilient homes that were outlined a couple weeks ago, unwanted heat gain will be very effectively controlled in the summer--as long as windows are closed during the hottest days.

Natural ventilation

Finally, we can achieve resilient homes that won't get too hot if power is lost and air conditioning doesn't work through natural ventilation. This strategy is particularly effective at night, when it's cooler outside than in. Simple operable windows with screens offer the primary strategy here, but we can go further. In hot, sunny climates, such as the Southwest, one can build solar chimneys that use the natural buoyancy of warm, rising air to pull in cooler outside air--sometimes through inlet tubes buried in the ground (earth tubes). Operable windows high on a wall or skylights can also serve as solar chimneys.

All of these natural cooling strategies can keep a house safe and reasonably comfortable in the summer during power outages. During normal times, such measures will significantly reduce the amount of time an air conditioner has to operate, while keeping the house more comfortable.

Alex is founder of BuildingGreen, Inc. and executive editor of Environmental Building News. To keep up with his latest articles and musings, you can sign up for his Twitter feed.

BIPV has yet to reach its full potential in the U.S., but a couple companies are giving it a shot.

Building-integrated photovoltaics (BIPV)--photovoltaic (PV) modules integrated into functional building elements, such as roofs, glazings, and building façades--are fairly common in Europe and Asia. Yet finding commercial BIPV façade products
in the U.S. is nearly impossible. Why is that?

There are a number of possibilities, including lack of suitable new projects due to the economy, a tempestuous PV market, and concerns about reliability and performance, to name a few--but the real reason might be a lot simpler.

Code compliance and bureaucracy

According to Steven Strong, president of Solar Design Associates, architects are not likely to design a façade around a BIPV manufacturer's standard PV panel offerings. The panels usually have to be custom-built for the project, and therein lies the problem.

In Europe, a custom PV panel built in the same manner as the manufacturer's standard-size offerings can be preapproved by CE or TÜV, manufactured, and installed with relatively little fanfare...or expense. Not so in the U.S. John Wohlgemuth, principal scientist in PV reliability at NREL, who also works on PV code compliance, said "You need UL 1703 to put any PV on a building, and UL 1703 says if you make any change in the module you have to reassess it."

This means a PV manufacturer has to get UL 1703 approval for each PV panel size. And if it is a custom panel, then the mounting system and components also need UL approval. It is a time-consuming, expensive process that "is a huge barrier to innovation and implementation," said Strong.

Hope for the future

But change is in the works. Wohlgemuth said that UL 1703 is being modified to better accommodate custom BIPV, and ultimately it will be replaced by IEC61730, which will eliminate the retesting requirement. The modifications to UL 1703 should be ready by the end of 2012, but it will be a couple years before IEC61730 is adopted and BIPV implementation is simplified in the U.S.

Soltecture and Focus Materials enter the BIPV market

While we wait for IEC61730, the German company Soltecture, formerly Sulfurcell, recently received UL approval for its Corium BIPV and is now offering it for sale in the U.S. The system uses the company's Linion L laminated copper indium gallium diselenide (CIGS) rigid thin-film PV panel adhered to an aluminum "cassette." The cassette attaches to the building's cladding system to give the frameless PV panel the appearance of black architectural glass. CIGS can provide decent performance in indirect light, so it's an appropriate choice for BIPV, which is often not ideally oriented to the sun. Corium is available in one size, 2' x 4', so there will be some design limitations, but it is smaller than most PV panels, so the company claims it should be easier to integrate into a building. And where irregular panels are required, matching black glass is used.

Soltecture's standard, non-Corium panels can also be used along with Focus Materials' UL-approved rainscreen and curtainwall BIPV mounting systems. Focus Material's offers a package that includes materials, gaskets, sealants, PV panels, wiring harnesses, and inverters as well as support.

Rapid industry changes

Over the last year or so, we've been busy trying to stay on top of the ever-changing photovoltaic (PV) industry--Evergreen Solar, BP Solar, and Uni-Solar have all gone out of business--so it is encouraging to see a new player enter the U.S. market, especially the BIPV market.

We've reorganized some of our GreenSpec BIPV sections to reflect the recent changes, and we hope to add more BIPV façade products as U.S. standards catch up with those in the rest of the world.

Passive solar design is a key element of creating resilient homes.

As I discussed in last week's blog, a resilient home is extremely well-insulated, so that it can be kept warm with very little supplemental heat--and if power or heating fuel is lost, for some reason, there won't be risk of homeowners getting dangerously cold or their pipes freezing. If we design and orient the house in such a way that natural heating from the sun can occur, we add to that resilience and further reduce the risk of the house getting too cold in the winter.

Passive solar heating

I had the good fortune of working in Santa Fe, New Mexico for a solar energy organization in the late-1970s, when the passive solar energy movement was just emerging. Northern New Mexico was the epicenter of research into passive solar--the effort, ironically, being led by Los Alamos National Laboratory, which, a generation earlier, had brought us the nuclear age.

It was an exciting time. The relationship between solar gain and thermal storage was becoming understood. It was discovered that very simple south-facing windows and high-mass walls and floors were not only far simpler than the very complex active solar heating systems that emerged (briefly) in the early 70s, but they also worked better. Direct-gain passive solar

The most common passive solar heating system is known as direct-gain. South-facing windows transmit sunlight that is absorbed by dark surfaces of high-mass materials in the house. In a sense, the house itself becomes the solar collector and heat storage system, with different components serving multiple functions. Those windows also provide views to the outdoors and bring in natural daylighting, while the thermal mass consists of the walls or floors that serve structural functions. We need those elements anyway, but by optimizing their area, placement, and configuration, they can become the primary heating system.

The challenge with direct-gain passive solar heating is to provide the right amount of glass in the proper orientations and incorporate the proper amount of thermal mass to minimize temperature cycling and prevent overheating. (Back in New Mexico in the late-1970s, there were a lot of poorly designed passive solar homes that overheated horribly.)

As window glazings have improved in the three decades since my days in New Mexico and as we have recognized the primary importance of highly insulated buildings (see last week's blog), the opportunities for passive solar heating have improved--but so has the complexity. With better glazings and reduced heat flow out of homes, one has to be more careful to prevent overheating or unacceptable temperature cycling. And we have to choose glazings more carefully, because the most insulating low-e glazings block too much of the solar gain. For passive solar, we want glazings with high solar heat gain coefficient (SHGC) ratings--values over 0.6 are great, but 0.5 should be considered a minimum when passive solar heating is important.

Fortunately, as the complexity has increased, the computer software tools for modeling energy performance of homes with significant solar gain have also improved. Such programs as Energy 10, EnergyPlus, and REM Design all do a good job at modeling energy performance and passive solar contributions to heating. With any such software, the designer inputs a location close to where the house is located to load the relevant solar gain and other climate data. Note that even with state-of-the-art software, hiring a designer with experience in passive solar design is key to achieving good performance.

Trombe walls

Direct-gain is the most common passive solar energy system, but it isn't the only one. With indirect-gain passive solar, the collection is only indirectly connected to the living space. The most common such system is a Trombe wall--a south-facing high-mass masonry wall with glass or plastic glazing held away from the wall in a frame. Sunlight shines through the glazing and heats the dark surface of the masonry wall. Heat moves into the wall where it is stored and gradually conducts through to the interior, where it radiates heat to the living space.

Some experts question whether it's better to simply add more insulation to that south wall and skip the indirect solar gain, while others argue that the solar is very important--especially relative to resilience. If other energy inputs to the house become unavailable for some reason, delivering heat with a Trombe wall could be very beneficial.

Sunspaces

Finally, there are isolated-gain passive solar systems in which solar heat is collected in one place and brought into the house only when desired. A south-facing attached sunspace is the most common isolated-gain system. The sunspace heats up during the day and windows or vents connecting the house and sunspace can be opened to deliver heat into the house, or kept closed to keep that heat out. An insulated wall between the house and sunspace ensures that as the sunspace cools off at night (due to heat loss through the large amount of glass), it won't cool the house down. The sunspace serves as a heating system for the house, even as it also serves as a supplemental daytime living area and a place to grow plants (especially plants that can accept significant temperature cycling).

Passive solar and resilience

No matter which type of passive solar heating system is employed, it plays a key role in making a house resilient to power interruptions and loss of heating fuel. If there is no solar gain, even a highly insulated house will gradually cool off. The more insulation, the slower the temperature in the house will drop, but drop it will. With a reasonable amount of passive solar gain and a really well-insulated building envelope, enough heat will enter the house to compensate for most of that heat loss in all but the cloudiest weather.


In this resilient design series, I'm covering how to achieve resilient homes and communities, including strategies that help our homes survive natural disasters and function well in the aftermath of any event that results in an extended power outage, interruption in heating fuel, or shortage of water. We'll see that resilient design is a life-safety issue that is critical for the security and wellbeing of families in a future of climate uncertainty and the ever-present risk of terrorism.

Alex is founder of BuildingGreen, Inc. and executive editor of Environmental Building News. To keep up with his latest articles and musings, you can sign up for his Twitter feed.

What's in it? Where was it made? Is the manufacturer socially responsible? These questions about green building products are getting easier to answer.

This is Part 1 in our series on transparency.

Part 2: Why We Need "Nutrition Labels" for Building Products

Part 3: The End of Greenwashing? Five Myths about Product Transparency

There's been a growing amount of buzz recently about "transparency"--a catchy word for giving people more information about products, finances, corporate behavior, and more.

It looks to us like the move toward transparency will be a major theme in 2012, so we focused EBN's January feature on explaining different forms of transparency and what this that could actually mean for the building industry in practice. To whet your appetite, check out this quick video we put together for a taste of what transparency means and how it could change our lives (thanks to our multi-talented sales administrator, HB Lozito, for her brilliant animations and narration).

Highlighting transparency in GreenSpec

We're also going to make it easier to find products from companies that are taking the lead in providing greater information transparency about their products and activities. Starting today, GreenSpec will have a new Green Attribute for Information Transparency.

This means you'll be able to go directly from the "Green Attributes" menu to a list of products---products that have an Environmental Product Declaration, provide full disclosure on product ingredients, or where the company is providing info about their total operations through systems such as the Global Reporting Initiative.

When you're searching for a specific product, you can also filter for just those in the set of products you're considering that have this greater level of transparency.

We'll be adding products over time, so don't expect to see a complete list just yet, but check it out, and let us know what you think. Are you already seeking out this level of information and just waiting for it to become standard practice? Are you skeptical of its value, and find information overload just getting worse? Somewhere in between?

From better data to better products

Of course, better information alone doesn't make a product green, but it does make it a lot easier to see just how green that product actually is. We can make more informed purchasing decisions when we know what's in a product--not just manufacturers' claims about what it's "free of"--and when we know the actual environmental impacts of manufacturing the product relative to alternatives, not just a trade association's claim that it's "green."

A product isn't going to get into GreenSpec just because the manufacturer gives us more information. But information transparency helps us decide if it's green enough for GreenSpec. It certainly saves us a lot of digging, and the whole point is that it should save you time too.

P.S. As far as GreenSpec is concerned, this is a bit of a sneak preview, as we'll be rolling out other new attributes this year. Next up in EBN: a complete revisiting of our popular "What Makes a Product Green?" article, last updated in 2006. GreenSpec's green attributes will be changed to reflect the guidance we outline there.

Nutrition labels allow shoppers to compare two bags of chips. The transparency movement seeks that level of transparency for building materials.

This is Part 2 in our series on transparency.

Part 1: Why We Care About Product Transparency

Part 3: The End of Greenwashing? Five Myths about Product Transparency

Building product transparency has been a hot topic in the design and construction world lately.

Pioneering manufacturers like InterfaceFLOR are releasing environmental product declarations (EPDs). Influential firms like Perkins+Will are gathering and publishing more data about what's really in our building materials (if you haven't seen the firm's new Transparency website, check it out here).

The LEED 2012 drafts are looking to incentivize transparency by offering credits for the use of products that have an EPD. We're also adding product transparency to GreenSpec as a searchable attribute to help you when specifying products.

As a companion to this month's EBN feature article, "The Product Transparency Movement: Peeking Behind the Corporate Veil," we've put together this fun four-minute video on what the transparency movement is all about. (Cheeky animations and soothing narration by our amazing sales administrator HB Lozito.)

We had a lot of fun making it, and folks have told us it's also fun to watch. Enjoy!

A resilient home is a highly energy-efficient home that will maintain livable conditions even during power outages or interruptions in heating fuel.

When most people think about resilience--resilience to storms or terrorism, for example--they think only about resilience during the event. Equally important, if not more important, I believe, is resilience in the aftermath of that event. Hurricanes, ice storms, blizzards, wildfires, tornadoes, and other natural disasters not only have an immediate impact, for which we may or may not be able to prepare, but they often have a much longer-term impact, usually through extended power outages.

The same goes for terrorist actions; some suggest that smarter terrorists of the future may target our energy infrastructure or hack into power system controls to wreak havoc (cyberterrorism).

In achieving resilience, I believe that our single most important priority is to ensure that our dwellings will maintain livable conditions in the event of extended power outages or interruptions in heating fuel. (I used to refer to this as "passive survivability," but I came to realize that that term was too negative or dire-sounding to get much buy-in.) Here in Vermont, a resilient home is one that will maintain temperatures of, say, 50 degrees Fahrenheit without supplemental heat. The most important strategy for ensuring that those livable conditions will be maintained is by creating highly insulated building envelopes. I will cover other strategies, such as passive solar heat and solar electricity, in future blogs in this series. Below are the key strategies for achieving exceptionally good energy performance:

Insulate extremely well

We used to think that 2x6 walls insulated with fiberglass or cellulose were perfectly adequate relative to R-value--even defining that house as energy-efficient compared with standard construction (insulated 2x4 walls). It takes far more insulation to achieve the level of resilience needed to ensure that the house will maintain livable conditions without supplemental heat or electricity.
Building Science Corporation, of Westford, MA recommends the 10-20-40-60 rule-of-thumb for insulation levels in homes in cold climates (roughly defined as homes north of the Mason-Dixon Line). This rule of thumb refers to R-10 for basement sub-slab insulation, R-20 for foundation walls, R-40 for above-grade walls, and R-60 for ceilings or roofs. That's a lot of insulation, compared to typical "energy-efficient" practice, which might include no insulation under a floor slab, R-5 to R-10 on foundation walls, R-19 in walls, and R-30 in attics.

Getting to these insulation levels is not easy. R-10 slab insulation requires two inches of extruded polystyrene or 2.5 inches of expanded polystyrene. R-20 foundation walls require four or five inches on the foundation exterior or an insulated 2x6 wall on the interior. Here are two options for achieving R-40 walls: double 2x4 walls held apart enough to achieve a ten-inch cavity and insulating with dense-pack cellulose; or insulating 2x6 studs with cellulose and then adding three inches of polyisocyanurate on the exterior. R-60 in an attic floor requires about 18 inches of cellulose.

For more on insulation materials (a lot more!), you might be interested in my recently published report: Insulation Materials: The BuildingGreen Guide to Products and Practices. It's available as a downloadable PDF file for $129.  

Install top-performing windows

This level of energy performance calls for windows that achieve a unit insulating value of R-5--that's not the center-of-glass R-value, but the average R-value for the entire window, including edges and frame. National Fenestration Rating Council (NFRC) window energy performance labels list U-factor rather than R-value. (U-factor is the inverse of R-value.) Look for an NFRC-rated U-factor of 0.20 or lower.

To achieve such superb energy performance typically requires triple glazing (three layers of glass or two layers of glass and a suspended plastic film) and at least one, but sometimes two, low-emissivity (low-e) coatings and low-conductivity gas in the space between the layers of glass. You can find windows today with unit U-factors as low as 0.15 (R-6.7). Such windows aren't cheap, but they are increasingly available, and they do a great job at keeping energy consumption down and ensuring comfort.

Very tight construction

Really well-insulated buildings should also be airtight. We don't want uncontrolled air leakage bringing outside air in through the walls or basement; we want to be able to control where fresh air is brought in through a properly designed ventilation system. The Passive House certification program, which originated in Germany but is gaining traction worldwide, including in the U.S., requires airtightness of 0.6 air changes per hour at 50 pascals of pressure difference. (We measure air tightness using a "blower door" and often report that air tightness as an elevated pressure of 50 pascals.) I think a reasonable airtightness level for new construction is 1.0 air changes per hour at 50 pascals--not quite as tight as the Passive House standard.

In the event of loss of power so that the ventilation system stops operating, windows can be cracked to provide fresh air, but most of the time ventilation systems should be operated to ensure good air quality in the home.  

New vs. existing homes

Achieving highly insulated building envelopes is much easier with new construction than with existing homes. To achieve such performance with an existing home requires what is often referred to as a "deep energy retrofit." More on that in a future blog.

In this resilient design series, I'm covering how to achieve resilient homes and communities, including strategies that help our homes survive natural disasters and function well in the aftermath of any event that results in an extended power outage, interruption in heating fuel, or shortage of water. We'll see that resilient design is a life-safety issue that is critical for the security and wellbeing of families in a future of climate uncertainty and the ever-present risk of terrorism.

Alex is founder of BuildingGreen, Inc. and executive editor of Environmental Building News. To keep up with his latest articles and musings, you can sign up for his Twitter feed.

USGBC's Center for Green Schools lauds ten groups for taking the lead on green building education.

My first lesson in how insulation works came during high school physics class--but not as part of an experiment.

Our physics lab was in the chilly basement, and the "lesson" consisted of Sister Bernie explaining to a shivering classmate that we should all come to physics class with extra layers because "dead air is the best insulator."

It was the old admonition to put on a sweater packaged as an explanation of why putting on a sweater actually works: the air trapped between two layers of clothing is what really keeps you warm--not so much the cloth itself.

Green building across the curriculum

For so many reasons, school is a great place to learn about green building. This is true even if you go to school in a rather dark 1930s-era masonry building, but more and more school districts are renovating and building for high performance, increasing opportunities for great conversations on the topic.

For a really cool example of integrating green building and education for even the youngest tykes, check out this kindergarten building, where five- and six-year-old kids learn about fluid dynamics by pedaling a tricycle.

Center for Green Schools awards

The Center for Green Schools, a project of the U.S. Green Building Council (USGBC), has started giving out awards for this kind of creativity, and the recipient list contains a few surprises.

Who knew that my home state (Ohio) was at the forefront of building high-performance schools? Did you know that Philadelphia is planning to make every one of its 291 schools green? And have you seen the really cool design of the student center at UT–Dallas?

Who's who in green schools

Read on for the complete list of awards--and check out full stories about each winner on the Center for Green Schools website. Congratulations to all!

• Best Moment for the Movement--U.S. Department of Education, for its Green Ribbon Schools Program
• Best Region--Sacramento area, for an innovative loan program for green school retrofits
• Best State--Ohio (Go Bucks!), for the largest number of green school projects under way
• Best City--Philadelphia, for making major strides toward an ambitious green school goal
• Best School--Lake Mills Middle School, the first public school in the nation to achieve LEED Platinum
• Best Higher Ed Innovator--University of Texas at Dallas, for its LEED Platinum student services building
• Best Collaborator--Kentucky General Assembly, for crossing party lines to adopt green school resolutions
• Best Convenor--Boston, for bringing together interdisciplinary researchers to study the connection between schools and student health
• Best Policy Maker--District of Columbia, for passing the legislation requiring healthy school buildings
• Best K–12 Innovator--Illinois General Assembly, for a private/public partnership to renovate three existing school buildings

Windows, carpet chemicals, spray-foam, and LEED lawsuits: these are a few of your favorite things.

It's been a big year for green building. People are tightening up their buildings even as they tighten their belts. The retrofit market and multifamily housing have taken off in a big way in this new financial landscape.

The most-read Environmental Building News articles of 2011 reflect these new realities. Please check them out below and tell us in comments what you'd like us to cover in 2012! Don't forget that you can also get continuing education credits for reading many of these articles.

(NB: many of our most popular articles are available for BuildingGreen members only. You can check out affordable membership options here.)

10. Better Choices in Low-Slope Roofing. There are big differences in environmental impacts of commercial roofing materials, but the biggest variable may be service life.

9. Energy-Efficient Multifamily Housing. Now you can get LEED, Energy Star, and other labels for designing or retrofitting high-performance multifamily buildings.
8. The Chemicals in Our Carpets and Textiles. The array of water-, dirt-, and mold-repellent chemicals added to carpeting and fabrics is dizzying. Which are causes for concern, and how can we minimize exposure?
7. Measuring Energy Use in Buildings: Do Our Metrics Really Add Up? How much energy our buildings use matters a great deal, but figuring out how to measure that use and compare it from building to building is tricky. Here's a guide to key metrics and how to use them.
6. EPA Takes Action on Spray-Foam Health Risks. EPA takes another look at spray foam after increasing consumer health complaints. The action plan leaves open questions about how far EPA will go to clamp down on these products, but it's safe to think of this as a shot across the bow from EPA for the SPF industry.
5. New Plaintiffs Join Amended LEED Lawsuit. Instead of seeking to establish a broad class-action lawsuit representing building owners, taxpayers, and professionals harmed by LEED, the amended lawsuit focuses on the latter. The lawsuit was dismissed later in the year.
4. Re-Framing Sustainability: Green Structural Engineering. Want to design the greenest building possible? Get a handle on the best structural options available to you, and invite a creative structural engineer to join your team.
3. Solar Thermal Hot Water, Heating, and Cooling. By creating heat instead of electricity, solar thermal achieves three times the efficiency of photovoltaics at a lower price.
2. Making Windows Work Better. How to choose curtains, solar screens, awnings, and storm windows? The options are dizzying, but the right choice can cut energy bills.
1. Choosing Windows: Looking Through the Options. We ask a lot from windows: energy efficiency, aesthetics, durability, affordability, and more. Which window frame materials and low-e glazing options balance these choices best? This article explores all the options and decodes the performance labels we see when buying windows.

As we look to create homes and communities that will keep us comfortable and safe in a world of climate change, terrorism, and other vulnerabilities, there are a handful of strategies that I group loosely under the heading of "smarter design." Some of these strategies come into play more at the land-use planning scale, or are relevant only in certain locations that are at risk of flooding, but all are worth thinking about when planning a new home.

Where we build

Following Hurricane Katrina's flooding of New Orleans in 2005, I got involved in an effort to guide the reconstruction that would occur--shifting it towards more sustainable practices. But the very idea of spending billions of dollars to rebuild in a place that is already below sea level at a time when sea levels are projected to rise seemed a mistake. I wrote at the time:

"In many respects, New Orleans should not be rebuilt in its present location--a lowland bowl situated between a lake and a river channel where this largest of America's rivers forms its delta. ...Serious consideration should be given to the idea of relocating the city to stable land, either somewhat inland from the coast or farther from the delta where it can be better protected. But there's almost no chance of that happening. New Orleans will be rebuilt where it is. Our nation has learned a lot in its 200-plus years, but we're neither that smart nor that bold."

We need to keep this discussion active. Whether it's about low-lying coastal areas prone to hurricanes, river floodplains in the Midwest that seem to flood every few years, or valley towns in Vermont prone to flash floods, we should be asking ourselves why we continue to rebuild in places that will again be damaged by flooding.

And it's not just flooding that should concern us. Each summer, when we read about wildfires in the fire-adapted chaparral country of southern California, we should ask ourselves why we keep building in places that keep burning. The frequency of those wildfires is expected to increase as climate change dries out that part of the country.

While we may not be able to change land-use laws to fully restrict building in places prone to flooding, fires, and other disasters, we can certainly make those decisions on our own--and not build in vulnerable places. While suitability for development is still often gauged by the 100-year flood elevations, we should be even more conservative and avoid places that are in the 500-year flood elevation. While Vermont's valley towns are attractive, we should build our houses and roads well above the valley floors. We should try to shift people from the Midwestern river floodplains to higher-elevation areas, increasing density in those safer areas through infill housing.

Elevating living spaces and equipment

In any area remotely vulnerable to flooding, elevating the living space above the potential flood elevation will dramatically reduce damage in the event of flooding. As is commonly done in coastal construction, ground-level spaces can be designed to be inundated with water and dry out. Break-away panels can also reduce damage in the event of flowing water--as in a flooded steam or river.

Basements should be avoided where there is risk of flooding, but even when flooding isn't a concern, it makes sense to elevate all mechanical equipment above a concrete-slab basement floor. A burst water pipe or the failure of a dishwasher or clothes washer can dump thousands of gallons of water that will find its way down to the basement. Elevating boilers, furnaces, water heaters, electrical panels, and any other equipment can dramatically reduce damage. It just makes sense.

Wettable materials

Just as we should elevate equipment so it doesn't get wet in the event of a flood, in locations where flooding could conceivably occur we should use materials that can survive wetting without significant damage. Paper-faced drywall, any kind of wood flooring or subflooring, and wall-to-wall carpeting, for example, should be avoided in finished basements.

Instead, consider polished concrete slabs as finished floors, metal studs for interior frame walls in basements, insulation materials that can get wet and dry out (such as rigid mineral wool and polyisocyanurate), and fiberglass-faced or non-paper-faced drywall.

More compact homes

Building smaller houses makes sense for a lot of reasons: less resources to build them, smaller footprint on the land, and less energy to operate. From a resilience standpoint, if power is lost for an extended period of time or heating fuel becomes scarce or supplies cut off, smaller houses are easier to keep safely warm in the winter months using a wood stove or gas-fired space heater (some don't require electricity to operate, because they have pilot lights and pezioelectric-powered thermostats).

I'll get into more on minimizing heating and cooling loads next week--and why that's such a critical resilient design strategy.


In this resilient design series, I'm covering how to improve the resilience of our homes and communities, including strategies that help our homes survive natural disasters and function well in the aftermath of such events or other circumstances that result in power outages, interruptions in heating fuel, or shortages of water. We'll see that resilient design is a life-safety issue that is critical for the security and wellbeing of families in a future of climate uncertainty and the ever-present risk of terrorism.

Alex is founder of BuildingGreen, Inc. and executive editor of Environmental Building News. To keep up with his latest articles and musings, you can sign up for his Twitter feed.

Double the fun by reading your favorite EBN articles to help you meet your LEED CMP requirements!

Looking for ways to meet your "prescriptive" continuing education (CE) requirements with the LEED Credential Maintenance Program (CMP)? Here at BuildingGreen.com we have long offered articles to help you earn your credits--articles that will truly help you learn cutting-edge green building information.

But meeting those LEED CMP requirements for GBCI can still be tricky, so we are providing this handy guide. As you're looking for hours to meet each of the various prescriptive requirements, here are suggested courses that you can use. Please read, learn, and earn!

By the way, not sure what these prescriptive requirements are all about and if they apply to you? Feel free to post questions below in the comments section, and also download the CMP guide from GBCI.

Project Site Factors

The Cost of LEED Certification (1 LEED-Specific CEU; AIA HSW/SD)

The Problem with Net-Zero Buildings (and the Case for Net-Zero Neighborhoods) (1 CEU; AIA HSW/SD)

Reexamining Priorities in Green Building (1 CEU; AIA HSW/SD)

Sustainable Sites: Primers from Environmental Building News (1 CEU; AIA HSW/SD)

Design for Adaptation: Living in a Climate-Changing World (1.5 CEUs; 1 AIA HSW/SD LU)

LEED 2012 Second Public Comment Period Opens (1 CEU; AIA HSW/SD)

Water Management

The Cost of LEED Certification (1 LEED-Specific CEU; AIA HSW/SD)

The Problem with Net-Zero Buildings (and the Case for Net-Zero Neighborhoods) (1 CEU; AIA HSW/SD)

Reexamining Priorities in Green Building (1 CEU; AIA HSW/SD)

Sustainable Sites: Primers from Environmental Building News (1 CEU; AIA HSW/SD)

Design for Adaptation: Living in a Climate-Changing World (1.5 CEUs; 1 AIA HSW/SD LU)

Cost-Effective Green Retrofits: Opportunities for Savings in Existing Buildings (1 CEU; AIA HSW/SD)
LEED 2012 Second Public Comment Period Opens (1 CEU; AIA HSW/SD)

Project Systems & Energy Impacts/ ND: Neighborhood Systems & Impacts

LEDs: The Future Is Here (1 CEU; AIA HSW/SD)

Occupant Engagement–Where Design Meets Performance (1 CEU; AIA HSW/SD)

Better Choices in Low-Slope Roofing (1 CEU; AIA HSW/SD)

Insulation: The BuildingGreen Guide to Insulation Products and Practices (6 CEUs; AIA HSW/SD)

Solar Thermal Hot Water, Heating, and Cooling (1 CEU; AIA HSW/SD)

LEED 2012 Second Public Comment Period Opens (1 CEU; AIA HSW/SD)

Ten Strategies for Growth in a Recession (1 CEU; AIA HSW/SD)

Energy-Efficient Multifamily Housing (1 CEU; AIA HSW/SD)

Making Windows Work Better (1 CEU; AIA HSW/SD)

Measuring Energy Use in Buildings: Do Our Metrics Really Add Up? (1 CEU; AIA HSW/SD)

Re-Framing Sustainability: Green Structural Engineering (1 CEU; AIA HSW/SD)

Choosing Windows: Looking Through the Options (1 CEU; AIA HSW/SD)

The Cost of LEED Certification (1 LEED-Specific CEU; AIA HSW/SD)

Video: Eight Steps to Success with LEED-EBOM  (1 LEED-Specific CEU; AIA HSW/SD)

The Problem with Net-Zero Buildings (and the Case for Net-Zero Neighborhoods) (1 CEU; AIA HSW/SD)

Reexamining Priorities in Green Building (1 CEU; AIA HSW/SD)

Retrocommissioning: Big Savings for Big Buildings (1 CEU; AIA HSW/SD)

Making Your Own Electricity: Onsite Photovoltaic Systems (1 CEU; AIA HSW/SD)

The Building Envelope: Primers from Environmental Building News (1 CEU; AIA HSW/SD)

Rethinking the All-Glass Building (1 CEU; AIA HSW/SD)

Counting Carbon: Understanding Carbon Footprints of Buildings (1 CEU; AIA HSW/SD)

Design for Adaptation: Living in a Climate-Changing World (1.5 CEUs; 1 AIA HSW/SD LU)

Cost-Effective Green Retrofits: Opportunities for Savings in Existing Buildings (1 CEU; AIA HSW/SD)

Acquisition, Installation, and Management of Project Materials

LEDs: The Future Is Here (1 CEU; AIA HSW/SD)

Better Choices in Low-Slope Roofing (1 CEU; AIA HSW/SD)

Insulation: The BuildingGreen Guide to Insulation Products and Practices (6 CEUs; AIA HSW/SD)

Solar Thermal Hot Water, Heating, and Cooling (1 CEU; AIA HSW/SD)

LEED 2012 Second Public Comment Period Opens (1 CEU; AIA HSW/SD)

Making Windows Work Better (1 CEU; AIA HSW/SD)

The Chemicals on Our Carpets and Textiles (1 CEU; AIA HSW/SD)

Choosing Windows: Looking Through the Options (1 CEU; AIA HSW/SD)

EBN Editors Help Untangle Green Certifications (6 CEUs; AIA HSW/SD)

The Cost of LEED Certification (1 LEED-Specific CEU; AIA HSW/SD)

What's New in Multi-Attribute Environmental Certifications (1 CEU; AIA HSW/SD)

Reexamining Priorities in Green Building (1 CEU; AIA HSW/SD)

Making Your Own Electricity: Onsite Photovoltaic Systems (1 CEU; AIA HSW/SD)

The Building Envelope: Primers from Environmental Building News (1 CEU; AIA HSW/SD)

Sustainable Sites: Primers from Environmental Building News (1 CEU; AIA HSW/SD)

Rethinking the All-Glass Building (1 CEU; AIA HSW/SD)

Design for Adaptation: Living in a Climate-Changing World (1.5 CEUs; 1 AIA HSW/SD LU)

Cost-Effective Green Retrofits: Opportunities for Savings in Existing Buildings (1 CEU; AIA HSW/SD)

Improvements to the Indoor Environment

LEDs: The Future Is Here (1 CEU; AIA HSW/SD)

Insulation: The BuildingGreen Guide to Insulation Products and Practices (6 CEUs; AIA HSW/SD)

LEED 2012 Second Public Comment Period Opens (1 CEU; AIA HSW/SD)

Energy-Efficient Multifamily Housing (1 CEU; AIA HSW/SD)

Making Windows Work Better (1 CEU; AIA HSW/SD)

The Chemicals on Our Carpets and Textiles (1 CEU; AIA HSW/SD)

The Cost of LEED Certification (1 LEED-Specific CEU; AIA HSW/SD)

Reexamining Priorities in Green Building (1 CEU; AIA HSW/SD)

The Building Envelope: Primers from Environmental Building News (1 CEU; AIA HSW/SD)

Cost-Effective Green Retrofits: Opportunities for Savings in Existing Buildings (1 CEU; AIA HSW/SD)

Stakeholder Involvement in Innovation/ND: Stakeholder Involvement & Public Outreach

Occupant Engagement–Where Design Meets Performance (1 CEU; AIA HSW/SD)

LEED 2012 Second Public Comment Period Opens (1 CEU; AIA HSW/SD)

Ten Strategies for Growth in a Recession (1 CEU; AIA HSW/SD)

Energy-Efficient Multifamily Housing (1 CEU; AIA HSW/SD)

Re-Framing Sustainability: Green Structural Engineering (1 CEU; AIA HSW/SD)

The Cost of LEED Certification (1 LEED-Specific CEU; AIA HSW/SD)

Video:Eight Steps to Success with LEED-EBOM  (1 LEED-Specific CEU; AIA HSW/SD)

The Problem with Net-Zero Buildings (and the Case for Net-Zero Neighborhoods) (1 CEU; AIA HSW/SD)

Reexamining Priorities in Green Building (1 CEU; AIA HSW/SD)

Video: Insights to Success on LEED-CI Certification (1 LEED-Specific CEU; AIA HSW/SD)

Retrocommissioning: Big Savings for Big Buildings (1 CEU; AIA HSW/SD)

Making Your Own Electricity: Onsite Photovoltaic Systems (1 CEU; AIA HSW/SD)

Integrated Design Meets the Real World (1 CEU; AIA HSW/SD)

Counting Carbon: Understanding Carbon Footprints of Buildings (1 CEU; AIA HSW/SD)

Design for Adaptation: Living in a Climate-Changing World (1.5 CEUs; 1 AIA HSW/SD LU)

Cost-Effective Green Retrofits: Opportunities for Savings in Existing Buildings (1 CEU; AIA HSW/SD)

Project Surroundings & Public Outreach/ ND: Land Use and Urban Design

Occupant Engagement–Where Design Meets Performance (1 CEU; AIA HSW/SD)

LEED 2012 Second Public Comment Period Opens (1 CEU; AIA HSW/SD)

Ten Strategies for Growth in a Recession (1 CEU; AIA HSW/SD)

Energy-Efficient Multifamily Housing (1 CEU; AIA HSW/SD)

The Cost of LEED Certification (1 LEED-Specific CEU; AIA HSW/SD)

The Problem with Net-Zero Buildings (and the Case for Net-Zero Neighborhoods) (1 CEU; AIA HSW/SD)

Reexamining Priorities in Green Building (1 CEU; AIA HSW/SD)

Sustainable Sites: Primers from Environmental Building News (1 CEU; AIA HSW/SD)

Rethinking the All-Glass Building (1 CEU; AIA HSW/SD)

Design for Adaptation: Living in a Climate-Changing World (1.5 CEUs; 1 AIA HSW/SD LU)

Cost-Effective Green Retrofits: Opportunities for Savings in Existing Buildings (1 CEU; AIA HSW/SD)

Dear friends,

We know that the economic climate in 2011 has continued to be challenging, so we're all the more grateful and flattered that so many of you continue to rely on our tools and resources for insight, guidance, and community.

We're especially honored by the growth we've seen in enterprise licenses to firms and universities, illustrating the value of BuildingGreen Suite for bringing designers and students up to speed on core green building knowledge.

This past year was both challenging and exciting. Our efforts to serve you are continuing on many fronts, including our newly redesigned GreenSpec website, ongoing exploration of the latest topics in Environmental Building News, and steady growth of the amazing LEEDuser community (check out how much help people are getting and giving each other on the forums--it's free!).

With Alex Wilson on sabbatical for eight months, we proved that our team is robust enough to continue producing great resources through his absence. And we're excited to have him back, energized by the break from daily deadlines and motivated to reengage with our various initiatives, including an exploration of resilient design. Our collaboration with the Healthy Building Network extended beyond Pharos; we also joined them in launching the new Health Product Declaration--an open standard for reporting on product ingredients and health hazards.

We also continued working on research with Lawrence Berkeley National Lab on the energy and comfort benefits of various window attachments, created more case studies for ReGreen (the residential remodeling program), and provided technical guidance and content to GreenBuildingAdvisor and GreenSource magazine.

In our latest customer surveys we learned that you are looking for the latest on new developments in building science, materials research, energy modeling, BIM, and post-occupancy performance. Among larger firms integrative design is a particularly hot topic. We'll have these priorities in mind as we plan our upcoming articles and special reports.

As we dive into 2012 and beyond, we're more committed than ever to working with you to create the resources you need to keep transforming the building industry into a force for positive change. We've been true to that mission since we launched Environmental Building News 20 years ago, as the first dedicated green building publication. Please share your thoughts on how we can best support you and pursue that mission over the next 20 years!

Happy Holidays, and may your deepest wishes be fulfilled.

Nadav Malin
President
BuildingGreen, Inc.

For some fun around the holidays, GreenSpec is holding a virtual "open house"--giving you a sneak peek at some cool new products we're reviewing, and our first impressions. We'd like to hear what you think, so please read our first impressions below and then take the quick survey. Happy holidays! Update: Thank you for your feedback. We have closed the survey and are using it to inform our ongoing research agenda.