Compressible gaskets keep air and water barriers continuous without liquid sealants or adhesive tapes. But they don’t all last equally well.

This Holst Architecture-designed Passive House project, Karuna House, includes gasketing on the sill plate—common in Northern Europe for decades but fairly new to the U.S.
Photo Credit: Hammer & Hand

NOTE: Read this whole series here.

In the U.S., we tend to put a lot of faith in caulks, tapes, and wet-applied sealants. But in Europe it’s a different story.

Some Gaskets can be used in place of tapes or liquid sealants, mainly as part of residential air barrier systems. According to Lee Jaslow of Conservation Technologies, a leading U.S. distributor of high-performance gaskets and one of the high-performance gasket listings in GreenSpec, the market for gaskets in residential construction is small but growing, with increased interest due to high-performance rating systems such as Passive House.

A beautiful map of amazing places, why FSC is still best wood certification, and the scary story of why you should still make your own file backups.

My kids scrambled up the granite hill known as the South Bubble for the fourth or fifth time last week in Acadia National Park. Acadia is the only National Park we've been to, but after seeing the Sierra Club's "subway" map, we intend to change that ASAP.
Photo Credit: Paula Melton

Next stop, Yosemite

The Sierra Club has released an elegantly simple “subway map” of U.S. National Parks. How many stops have you made? See the map over at Treehugger and start your checklist.

FSC: Still the best

A great read on why FSC is still the best rating system for forestry products, although the others have improved. Perkins+Will recently reviewed its “FSC + Better” policy and decided to stick with it because “as a rule, FSC emphasizes real performance in the forest, whereas the other systems are more focused on intended outcomes,” writes P+W’s Doug Pierce. (For more context, see our series examining the “wood wars” in terms of economics, LEED credits, and global warming.)

Back up! And get your head out of the clouds!

Environmentalists have rushed to embrace cloud-based storage and computing practices, but let’s not get ahead of ourselves; aside from the serious energy issues to think through, we also need to back up our data in multiple places and think more carefully about security. This piece by Mat Honan at Wired reads like a thriller about the dangers of a purely digital life—but it’s frighteningly real. If you’re living in the cloud, be careful up there.

Finally fixing the basement drainage problems that have plagued my house for 30 years

I tried fixing the drainage years ago, but my fix failed at the basement window wells, including the one shown here on the back of the house after digging it out, exposing the EPDM drainage layer. Click to enlarge.
Photo Credit: Alex Wilson

When I bought the house in West Dummerston, Vermont, where my wife and I have lived for the past thirty years, one of the first things I did was fix the drainage problems that were dumping water into our basement….

Or so I thought. Let me explain.

When I moved into the 1780s house there was a hill on the west side that channeled runoff right into the dry-stone foundation. During rainstorms rivulets of water would flow into the basement with abandon. The house had only survived so long because the soil is very sandy. Moisture that got into the basement would quickly soak into the ground and disappear.

Step one was to change the topography. I hired an excavation contractor to move several hundred yards of earth from the west side of the house, creating a bit of a swale to direct runoff away from the house.

Caulk joint sealants can be a major deciding factor in how long your building envelope lasts. Is there a better way to predict how long they last?

Mounted on the roof at NIST, this "weathering engine" tests sealant durability.
Photo Credit: National Institute of Standards and Technology

NOTE: Read this whole series here.

Durability, or service life, is critical to the overall performance of liquid caulk joint sealants in the water and air barriers in our buildings.

If we can figure out how long sealants actually last then we can come up with a prudent inspection schedule—and have a good idea of how they’ll fail and how to replace them. The good news about sealants is that they are generally exposed to view—unlike flashing tapes, which are generally buried and inaccessible. (More on tapes in a future post.)

Fairly assessing durability or service life

We are always hoping for that one magic test that fairly, accurately, and realistically portrays one or more performance attributes of our building materials.

The trouble is that, while field tests can be more realistic, they tend to introduce many uncontrolled or non-measurable conditions. And the trouble with laboratory tests is that they set, control, and measure many conditions, making them often far from what actually goes on in the field.

It turns out that we have plenty of useful standardized laboratory tests for both liquid sealants and tapes that we use in our weather and air barriers. That’s the good news. The bad news is that we haven’t had useful tests for the field service life prediction of those same sealants and tapes—until recently.

Laws taking effect now are advertising the real energy performance of large buildings in cities like New York for all to see.

Monitoring your energy use isn’t just a good idea—it’s now the law in some cities and states. As we report on in our new EBN feature article, Energy Reporting—It’s the Law, the public is about to find out just how much energy is being consumed in thousands of large buildings in New York City, and similar laws are being enacted and taking effect in several other U.S. cities.

Benchmarking vs. Reporting: What’s the Difference?

Many of the laws that require energy reporting are called “benchmarking” laws. But actual benchmarking may or may not be part of the process. These key definitions should help cut through the confusion.

Introducing all-natural expanded cork boardstock insulation to the North American market.

Expanded cork insulation is available up to 12 inches thick and can be used much like polyiso. Click to enlarge.
Photo Credit: Amorim Isolamentos

I’m always on the hunt for the latest, most interesting, and most environmentally friendly building materials, and I have particular interest in insulation products—partly because many conventional insulation products have significant environmental downsides. (See “Avoiding the Global Warming Impact of Insulation” and “Polystyrene: Does it Belong in a Green Building?”)

So I was thrilled to learn about expanded cork boardstock insulation made by the Portuguese company Amorim Isolamentos and just now being introduced into the North American market. Francisco Simoes, of Amorim, visited our office in Brattleboro in June and told us all about it.

Familiar to wine drinkers as the traditional bottle-stopper, cork is a natural product made from the outer bark of a species of oak tree that grows in the western Mediterranean region of Europe and North Africa. The bark is harvested after trees reach an age of 18–25 years and it regenerates, allowing harvesting every nine years over the tree’s 200-year life.

Oregon-based Viridian upcycles shipping waste to make stylish flooring, tabletops, veneers, and other products

Once destined for the landfill, this wood was taken from shipping materials and upcycled into Viridian's Jakarta Market Blend flooring.
Photo Credit: Viridian Reclaimed Wood

Over the years, the GreenSpec team has looked at a lot of reclaimed lumber. It’s usually taken from barns and other aging structures, checked for lead paint and chemicals, and then turned into flooring and other products.

It’s rustic and attractive, but actually ordering it is fraught with supply challenges, so when Joe Mitchoff, co-founder of Viridian Wood Products, stopped by the office to show his company’s products to Alex Wilson and me, my expectations were not particularly high. I was, however, pleasantly surprised by the product and the story behind it.

The Process

Most of Viridian’s wood is not reclaimed from buildings. Instead, it comes from overseas shipping materials gathered from the Port of Portland, Oregon, and other area ports. Mitchoff and his business partner, Pierce Henley, discovered that the wooden pallets, crates, and other packing materials that came into the port everyday were sent to the landfill as a matter of course—up to thirty, 30-yard dumpsters per ship. “We found this tremendous waste at the Port of Portland,” Mitchoff said, and they began looking for ways to upcycle it.

Illustration: Tristan Roberts

“Anyone else finding a trend of clients wanting LEED-certifiable projects but not wanting to commit to certification? I have three projects just this week toying with going this route.”

That was the opening salvo in a recent email discussion I was involved in among a group of architects. With the permission of those involved, I’ve anonymously synthesized some of the key takeaways here. I’d also like to hear from you: please post your experiences on LEED certified vs. certifiable projects below.

It’s about the cost, stupid

The following comment summed up some of the objections out there to pursuing LEED: “We are seeing a little green fatigue as well internally and externally; somehow making a project ‘certifiable’ instead of certified seems less onerous and costly.”

Can top energy performance be achieved by combining fairly standard windows with really good storm windows or even a second set of prime windows?

A low-e storm window at my colleague Peter Yost's house in Brattleboro. Click on image to enlarge.
Photo Credit: Peter Yost

I’ve done a lot of digging into window options in the past few months—not only for a special report on windows that BuildingGreen published, but also for the renovation of the early-19^th-Century farmhouse that my wife and I recently purchased.

The state-of-the-art with windows in terms of energy performance and quality is clearly seen in the triple-glazed European windows that are certified by the Passivhaus Institut in Germany. You can now buy these wonderful windows with unit center-of-glass R-values above R-9 yet high-enough light transmission to work well for passive solar houses (solar heat gain coefficient above 0.60).

The problem is that these windows are incredibly expensive—some over $100 per square foot, which comes to $1,500 for a typical 3' x 5' window. You get a lot for that price in the way of top-quality materials, construction detailing, durability, thermal breaks, air tightness, and energy performance, but the windows are simply way above the budget range for most projects. Furthermore, replacing existing windows is often very hard to justify unless the existing windows are in very poor shape.

We’ve run the numbers from our quiz on toxic chemicals in building products, and we all have some explaining to do. Put down your #2 pencils and listen up!

SPOILER ALERT: If you haven’t yet taken the GreenSpec toxic chemical quiz, head over and do it now—yes, before you read the answers.

Find out how you did

Find out below how well you did on the GreenSpec toxic chemical quiz. And feel free to brag, commiserate, add your expertise, or kvetch about “trick questions” in the comments.

Afterwards, if you want to learn more about toxic chemicals in building materials—or if you are looking for a simple, straightforward way to share your knowledge with colleagues, students, or clients—please check out the report we've just released, Avoiding Toxic Chemicals in Commercial Building Products: A Handbook of Common Hazards and How to Keep Them Out.

Which one applies to you?

20–25 points: Consider a career change: you should be teaching toxicology summer school!

13–19 points: You have a pretty good handle on how to design healthier buildings—but the unknowns could keep you up at night.

6–12 points: You know just enough about toxic chemicals to be dangerous!

0–5 points: What you don’t know can hurt you: consider brushing up.