I attended the GreenBuild Conference and related meetings in San Francisco last week. This is the largest conference and trade show in the green building field, and it is increasingly becoming the national event where large manufacturers roll out new building products.
Described below are a few product highlights from the trade show that caught my eye as I wandered around. I only got through about a quarter of the trade show.
Wood-fiber insulation from Germany
In Europe it is becoming increasingly common to use high-permeability wood fiber sheathing as an exterior insulation material, and at least one such material was on display at the conference. The Small Planet Workshop in Olympia, Washington, is now distributing the German product Agepan THD. These 2-inch-thick panels insulate to R-5.7 (R-2.3 per inch) and have a high perm rating of 18 — meaning that water vapor can pass through them fairly easily.
It’s hard to say whether wood-fiber insulative sheathing will gain followers here, but there is growing interest in wall assemblies that won’t trap moisture, so products like these are worth keeping an eye on. The Small Planet Workshop also distributes the expanded-cork boardstock insulation that I’ve written about previously and that I’m planning to use on my own house in Dummerston, Vermont.
Vacuum insulation moving into the main stream?
Vacuum insulation has been around for a while, but it has never made inroads into the market — despite a major effort for Owens Corning to do so with its Aura panel way back in 1992. Dow Corning is going to give it a shot. After premiering its Vacuum Insulation Panel (VIP) at the Living Future Conference in May of this year (see BuildingGreen article and GreenSpec product page), the company made a bigger splash at Greenbuild.
Dow Corning’s VIP is sold in 24″ by 36″ panels in thicknesses from 1/4 inch to 1 1/2 inch. The panels have a fumed silica core that is 95% pre-consumer recycled content, wrapped with an aluminum skin, and 1-inch-thick panels provide an insulating value of R-39 (center-of-panel).
Dow Corning’s vacuum panel is being specified in commercial-building facades to insulate spandrel glass (in all-glass curtainwall buildings, the opaque glass that spans between glazing), but I believe the primary application for VIPs will be in appliance manufacturing where high insulation performance in thin layers is desired (refrigerators, freezers, and water heaters). A press release on the product with a link to a downloadable information sheet is found at this link.
A high-R-value coating with silica aerogel
Silica aerogel is a bizarre material. Aerogel the lowest-density solid known. It transmits light and insulates extremely well, owing to its molecular structure. For the past decade, the Cabot Corporation has produced silica aerogel granules under the brand name Lumira (previously Nanogel) that are used in daylighting panels that provide diffused light even while offering remarkably high insulating value (about R-20 in a 2 1/2-inch panel), and the material is also incorporated into a felt-like mat that can be used in roofing fabrics. Find Lumira in GreenSpec here.
At GreenBuild the company introduced a new formulation of silica aerogel, Enova, that can be added to paint to provide a thin, insulating coating. A very effective demonstration in the booth used a piece of aluminum that was half painted with this 2 mm-thick coating and half uncoated with a refrigerated space behind. You could feel the dramatic difference in temperature, since the aerogel coating significantly reduced heat flow through the material. A key benefit will be preventing condensation.
Zehnder’s top-efficiency HRV now certified by the Home Ventilating Institute
Zehnder is Swiss manufacturer of high-efficiency heat-recovery ventilators (HRVs) for whole-house ventilation. Represented in the U.S. by Zehnder America since 2010, the company is defining the future of high-performance ventilation. All of the company’s HRVs carry Passivhaus certification, and the company’s Novus 300 HRV recently earned certification with the Home Ventilating Institute (HVI).
Based on the HVI test methods, the Novus 300 achieves “apparent sensible effectiveness” of 94% to 96% and “sensible recovery efficiency” of 90% to 91%, significantly exceeding the performance of any other HRVs in the HVI Certified Products Directory. One of the company’s ComfoAir models (see GreenSpec product page) also carries HVI certification, and others in the line will be certified.
Alex is founder of BuildingGreen, Inc. and executive editor of Environmental Building News. He also recently created the Resilient Design Institute. To keep up with Alex’s latest articles and musings, you can sign up for his Twitter feed.