Designing, specifying, and constructing high-performance commercial building assemblies is a tall order. Lining up and integrating all of the components for continuous air and water barriers can be maddening. And whose job is this? It’s actually a chain of responsibility: architect, specifier, general contractor—and, finally, all the trades.

Where do the manufacturers of all the components fit in? They just make and sell stuff and then all the building professionals get to work it out, right? Not always—and certainly not if Tremco has anything to say about it. Tremco has patented and commercialized its Proglaze Engineered Transition Assembly (ETA) System as an integrated whole of compatible sealants, membranes, primers, and flashings (all its own products) with both insulation and sheathings (other manufacturers').

Rainwater capture seems more important every year as one region or another struggles with drought or other reasons for water shortage—which can even be caused by flooding (see “Resilient Design: Smarter Building for a Turbulent Future”). For this product survey, we sifted through numerous articles and our product database as well as through purveyors of rainwater harvesting systems and equipment both nationally and internationally.

What follows is by no means a comprehensive list of systems and products in the rainwater harvesting field, but the aggregation of representative products should convey the breadth and growth of this industry in recent years. Not included are the simplest rain barrel systems.

Turning night and day, a wind turbine can make electricity when solar panels can’t; perched on a tower over a green building, it can be poetry in motion. Unfortunately, performance depends a lot on the right site, which can be hard to come by. And while growing 26% annually in one recent period, the small wind market has been plagued by low-quality products and exaggerated claims from manufacturers. One study, a 2008 report on 19 small wind turbines installed in Massachusetts, found 60% worse performance than predicted (see “The Folly of Building-Integrated Wind,” EBN May 2011). A new wind is blowing in the small wind market, though: a reputable certification is being adopted, making it easier for consumers to understand their options, while new and old financing options are making it easier for consumers to consider small wind turbines.

Standard 9.1-2009 was developed by the American Wind Energy Association (AWEA) to eliminate misleading manufacturer claims and make it easier for consumers to accurately compare small wind turbines, which are defined as having a rotor swept area of up to 200 m2 (a radius of approximately 8m, or 26 ft.), usually with no more than 50–60 kW capacity. The standard has just begun to catch on, with two turbines certified to date and more on the way this year.

This photo shows production of the Skystream 3.7.

What is it about European windows that makes them so popular for ultra-low-energy Passive House projects? The glass is largely the same; in fact, American companies have led the development of low-e glazings. In a nutshell, it is the frames, gasketing, and hardware that separate top-quality European windows from their American counterparts. And, ironically, the testing standard used for American windows has to some extent held American windows back.

The National Fenestration Rating Council (NFRC) was established in the U.S. in 1989 to standardize the testing and reporting of window energy performance. Prior to the formation of NFRC, window manufacturers used different methods to report their performance. Consumers and specifiers couldn’t compare apples to apples. Among the most important performance metrics to be addressed by NFRC was the U-factor, the amount of heat flow through a whole window unit under certain testing conditions. U-factor is the inverse of R-value, and until NFRC came along, manufacturers most commonly reported energy performance as the center-of-glass R-value.

A new class of paint is emerging, rising to both performance and environmental challenges: waterborne alkyd paints.

Regular alkyd paints (also known as oil-based or solvent-borne paints) form a hard, glossy surface that is easy to clean and resists scratching, water, and chemicals. Used primarily for trim, doors, cabinets, furniture, floors, commercial walls, and other high-use areas, they are popular with professional painters because they adhere well to most surfaces and “level out” to hide brush marks and small surface irregularities, curing to a smooth surface that latex paints cannot match. Unfortunately, standard alkyds typically contain flammable, potentially toxic petroleum-based solvents that emit high levels of volatile organic compounds (VOCs). They require ventilation during application and petroleum distillates for cleanup, and excess paint has to be disposed of as hazardous waste.

Despite their drawbacks in terms of energy performance (see “Rethinking the All-Glass Building,” EBN July 2010), for many owners and designers curtainwall systems are an integral part of the design aesthetic for buildings large and small. Fortunately, curtainwall systems with higher thermal efficiencies, condensation resistance, and durability are increasingly available—and increasingly specified.

The largest curtainwall systems are typically custom-designed, site-assembled, and competitively bid, but at the medium to small scale, those seeking high-efficiency curtainwalls for projects may turn to companies that provide more standardized systems, whether factory-built unitized ones or site-assembled.

Concrete has great compressive strength but poor tensile strength. It is brittle, cracks, and doesn’t flex, which is why it is reinforced with steel—but steel corrosion is a primary source of concrete failure. Lafarge’s Ductal line of specialty ultra-high-performance concretes (UHPC) offers significant improvements in these areas, with a thin, lightweight, extremely durable concrete avoiding standard steel reinforcement.

Ductal is made from portland cement, silica fume (a byproduct of electric arc furnaces), silica flour, silica sand, water, and polycarboxolate high-range water reducers (superplasticizers) that help cement flow; Lafarge adds metal or polyvinyl alcohol fibers to provide structure. “All the materials in Ductal are standard products,” said Vic Perry, vice president and general manager at Lafarge North America. “It’s how we select them and put them together that makes Ductal work.” Lafarge controls the size, geometry, and orientation of all the materials “at the micro level,” in Perry’s words, to create a very dense matrix that can be formed into intricate shapes while maintaining its performance.

ULE ISR 100 provides a life-cycle-based approach to the evaluation of gypsum board—taking into account the material extraction and manufacture of the product as well as toxicity, durability, and end-of-life management.

“It’s a science-based standard,” said Bill Hoffman, Ph.D., a senior scientist at ULE. He was directly involved in the development of ISR 100, which he says relied heavily on data coming out of the gypsum industry. The standard also puts emphasis on continued data collection, with prerequisites and points based on life-cycle assessment (LCA), baseline data, and explicit disclosure of all ingredients down to 0.1%, or 1,000 parts per million (ppm), of the total product.

By Peter YostHydroGap, manufactured by Benjamin Obdyke, is an innovative new weather-resistive barrier (WRB), drainage space, and air barrier all rolled into one. This polypropylene-based, nonwoven housewrap has thermoplastic olefin (TPO) spacers that create a 1 mm (1⁄32") free-draining air space between cladding and sheathing. Because the space is so small, HydroGap permits standard detailing after installation, making it more fool-proof and less expensive than typical rainscreen products, which create gaps of 6 mm (1⁄4") or more and require special detailing.

“We filed for a patent back in 2006,” says George Caruso, Benjamin Obdyke’s product development manager. “We recognized that our rainscreen product [Home Slicker], while successful, was not reaching the full audience of builders interested in building better and managing moisture." (See “How Rainscreens Work,”

The Corium system consists of Soltecture’s Linion L laminated copper indium gallium diselenide (CIGS) rigid thin-film PV panel adhered to an aluminum “cassette.” The cassette is then attached to the building’s cladding system to give the frameless Linion L panel the appearance of black architectural glass. CIGS panels work better than crystalline PV at low sun angles—which is useful in maximizing the benefit of vertically mounted BIPV. Boris von Bormann, Soltecture’s director of sales for North America, claims that the company’s 100-watt modules have efficiencies of around 12.5%–13.0%, with 14.5% expected later this year. Soltecture received UL approval for its modules in October 2011 but does not have UL approval for its mounting system.

Steven Strong, president of Solar Design Associates in Massachusetts, says implementing BIPV in the U.S. is a significant challenge because of UL requirements. “The national electrical code requires that all PV components, especially modules, need to be listed to UL 1703,” said Strong. Standards in Europe, Japan, and China certify the