LED lighting keeps on improving as yet another record efficacy is announced.

Cree's new XLamp XP-G2 LED chip delivers up to 165 lumens per watt. Click on image to enlarge.
Photo Credit: Cree

A few days ago I got yet another press release about a new efficiency record with LED lighting. These are almost commonplace as we ride the revolution that is redefining electric lighting.

To back up, let me provide a short synopsis of lighting technologies and history.

Incandescent lamps provided the first electric lighting, with Thomas Edison inventing the first commercially viable light bulb around 1880 (building on the inventions of many others), and the technology has changed relatively little since General Electric introduced tungsten-filament light bulbs in 1911. Electric current flows through a very thin, coiled filament made of tungsten wire and glows white-hot, producing light. With incandescent lighting, roughly 90% of the electricity is converted into heat, only 10% into light.

The American Chemistry Council and other groups have formed the American High-Performance Buildings Coalition. Green or greenwash?

How many high-performance buildings on K Street?
Photo Credit: OpenSecrets.org

The American Chemistry Council (ACC) has opened a new front in its battle with LEED and the U.S. Green Building Council (USGBC)—one with similarities to greenwash tactics we’ve seen before.

ACC has formed a group dubbed the American High-Performance Buildings Coalition(AHPBC), joining 25 other industry groups representing building materials and products interests. The coalition includes names like the Vinyl Institute, the Vinyl Siding Institute, the Windows & Door Manufacturers Association, the Treated Wood Council, and the Adhesives and Sealants Council, as well as the U.S. Chamber of Commerce.

No more “arbitrary” restrictions!

As we’ve reported (see Chemical Industry Attacks LEED: BuildingGreen Checks the Facts), chemical and plastics trade groups have been making a recent pastime of claiming the federal government should stop using LEED and have been exerting their deep ties on Capitol Hill to pressure influential government groups like the General Services Administration (GSA) to stop using LEED.

The groups are apparently incensed over “arbitrary chemical restrictions” they perceive in LEED v4, the version of LEED currently under development, and are worried that LEED is “becoming a tool to punish chemical companies.”

According to its website, AHPBC:

… is composed of leading organizations representing a range of products and materials relevant to the building and construction industry who are committed to promoting performance-based energy efficiency and sustainable building standards. We support the development of green building standards through consensus-based processes derived from data and performance-driven criteria.

Understanding the options with room air conditioners, central air conditioners, and heat pumps.

The outdoor unit of a Daikin mini-split air-source heat pump in Putney, Vermont. Click to enlarge.
Photo Credit: Alex Wilson

I have never owned an air conditioner, and I don’t have any immediate plans to change that. But if I did, what would I look for?

For only occasional use and when you don’t want to spend more than $1,000, the options are limited to room air conditioners, which are most commonly installed in windows. These cool the rooms in which they are installed, though in a small house or one that’s very-well-insulated and tight, a single window unit may be able to cool much of the house.

Most room air conditioners are either installed in a double-hung window or in an opening in the wall specially created for the air conditioner. Special models are available that can be used in casement windows, though installation is trickier.

Green Globes may have come out slightly ahead in a recent “alignment” report, but support for LEED is strong in the building industry.

Atlantic Wharf, a huge mixed-use building on Boston's waterfront, is pre-certified LEED Gold and features a rain harvesting system to re-use rainwater in building systems and a green roof on the Waterfront Building.
Photo Credit: JC Cannistraro

The U.S. General Services Administration (GSA), along with the Department of Defense and Department of Energy, today hosted a second “listening session” on which green building rating system it should recommend for federal government use. Public comments almost universally favored a GSA determination to continue with LEED as the government’s rating system of choice.

This rating system review is stipulated by the Energy Independence and Security Act of 2007 and supported by a report from Pacific Northwest National Labs that compared LEED, Green Globes, and the Living Building Challenge. As reported in EBN, that report found that Green Globes aligned with federal guidelines slightly better than LEED for New Construction, while LEED bested Green Globes in that tally for existing buildings.

The first listening session took place in Washington, D.C., in late June; today’s happened online, where 25 speakers each got three minutes to speak. What they said was almost universally in support of LEED.

The Tally:

When you use tape to seal a seam or flash a sill, you need peel-and-stick performance—not “stick-and-peel.”

...or is it? Our confidence in tape might be a little misplaced.

NOTE: Read this whole series here.

While liquid sealants most often are used on the exposed surfaces of building enclosures, pressure-sensitive adhesive tapes (member link) and membranes are used one or even two layers deep in the building assembly to seal the margins of weather-resistive and air barriers and at penetrations such as window openings.

Their location means that they cannot be inspected, repaired, or replaced; we need to know that they will maintain their integrity and function for the full service life of the assembly.

What makes stuff “sticky?”

It’s pretty easy to take pressure-sensitive adhesion (PSA) for granted; from band-aids to masking tape to peel-and-stick membranes, we use them pretty much every day. But the science of PSA is complex and even a bit uncertain.

Take our quiz to find out how much you really know about VOCs, lead, toxic flame retardants, and other common hazards in building materials.

Sometimes you feel like you should wear a hazmat suit to the office—but it can be difficult to find a tie to match.
Photo Credit: Reena Rose Sibayan, NJ.com

Food, toys, furniture, building products—just about everything around us—can contain chemicals that will make us very sick or even kill us if we are exposed at a certain level over a long period of time. Sometimes it seems like there’s some new killer substance in our homes, schools, and offices almost every day of the week.

Information overload

But news stories about these products usually provide little or no context to help people understand when they may truly be in danger.

A lot of people, overwhelmed by the constant scares and unclear on which products are actually hazardous, give up on keeping track of everything that might poison them.

Building industry professionals don’t have that luxury.

Clients are paying attention, but they need your help

Knowing which building materials and products are likely to contain which toxic substances—and knowing when to minimize use of those materials or find less-toxic alternatives—comes with the territory. And the need for this knowledge is not just confined to the green building world anymore.

A look at the fascinating history and operation of refrigerant-cycle air conditioners.

Fedders room air 5,000 Btu/hour room conditioner. Click on image to enlarge.
Photo Credit: Fedders

My wife and I did the outside work early, while the weather was still bearable. Since mid-day we’ve been holed up in the house. It’s not exactly cool indoors, but we’ve had the house closed up and it’s about 15 degrees cooler than outdoors. If it gets much warmer, though, I admit that I’ll at least be thinking about getting an air conditioner—as I do every year for a few days during the hottest weather.

Readers of last week’s blog know that there are usually ways to avoid mechanical air conditioning (at least in Vermont)—though in places like Phoenix (where it was forecast to reach 109°F today), air conditioners are pretty-much a necessity.

So what is an air conditioner exactly, and how does it work?

Passive solar design features have helped define what energy-efficient buildings look like. Have newer design practices left them behind?

A home in St. Peter, Minnnesota, designed by Sarah Nettleton Architects features south-facing glass with exterior shade panels and lots of interior thermal mass. Click to enlarge.
Photo Credit: Don Wong

The state of passive solar heating, though built on timeless principles, has changed over the past several decades—as latest feature article in Environmental Building News describes.

Some 36 years ago, in the summer between my junior and senior years of college, I dipped my feet into the world of renewable energy. About 20 students from Ithaca College and Cornell University spent the summer trying to determine whether a farm outside Ithaca could become energy self-sufficient. This was three years after the 1973 oil crisis, and like a lot of people, we wanted to figure out how to wean ourselves from fossil fuels. The National Science Foundation supported the project.

In 1976 solar heating usually referred to complex, active-solar systems. Experimenters and back-yard inventors were putting solar collectors on their roofs and pumping solar-heated air through rock-beds to store the heat, or they were pumping antifreeze through roof-mounted flat-plate collectors to charge large insulated water tanks.

We experimented with some of those systems in our quest for energy independence, but we were also hearing about these low-tech, passive-solar designs being developed in the Southwest—especially northern New Mexico. We liked what we saw and put on our tool belts to build some of these passive systems we were reading about, including south-facing attached solar greenhouses (sunspaces).

Simple strategies to keep cool without the use of mechanical air conditioning.

A simple exterior window shade in Florida that doesn't interfere with window operation. Click on image to enlarge.
Photo Credit: Alex Wilson

Welcome to summer. Burlington, Vermont hit a record 97°F the other day, and my place in West Dummerston reached 93°, with high humidity. What’s the best way to stay comfortable in weather like this—assuming that you’re not using mechanical air conditioning?

First, it’s important to understand that the goal isn’t really about temperature; it’s about comfort. Some very simple strategies can help you remain comfortable even with high air temperatures.

Dress for the conditions

Light, loose-fitting clothes—and as few of them as possible—will help keep you cool in hot weather. Shorts, loose-fitting shirts, blouses, and dresses allow more air circulation next to your skin and will keep you cooler.

Many owners and municipalities are requesting LEED “certifiable” buildings from their design teams. How is a specifier to respond?

The ZGF-designed "Living Learning Center" at the University of Oregon was designed to the LEED Silver standard but did not apply for certification. Colleges & universities frequently take this approach.
Photo Credit: University of Oregon

In our experience with over 200 (real) LEED projects, we have seen four approaches.

Approach 1: Declare an early victory

The team completes the LEED scorecard and declares victory. There is no mention of LEED in the project manual and the contractor is asked to “make the right green choices.” There is no review of the scorecard after construction. While this is clearly a useless LEED approach, there are many who accept this result. In fairness, some are municipalities that are not able to mandate certification, others are architects who believe their professional training and personal commitment is the correct measure of sustainability.

Specifier’s Response: As always, at least include low-VOC products, high-performance products, and construction waste management in your specs.

Approach 2: Sprinkle in some requirements

The team completes the LEED scorecard, makes a determination of which design credits could be easily achieved, and includes only a few requirements in the specifications. Perhaps construction waste management, FSC-certified wood, and Green Label Plus carpet are sufficient to demonstrate some interest in sustainable design. Data-intensive credits such as recycled content, regional materials, and low-emitting materials are typically avoided. Again, the scorecard is not evaluated after construction.