LIVE image

The Greenbuild conference, as usual, was the place to find out about innovations in green building products.

Agepan THD wood-fiber insulative sheathing is now being sold by the Small Planet Workshop. Click to enlarge.
Photo Credit: Small Planet Workshop

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"-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 it 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 a quarter-inch to an inch-and-a-half. The panels have a fumed silica core that is 95% pre-consumer recycled content, wrapped with an aluminum skin, and 1"-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" 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.

If you enjoyed this article, sign up for BuildingGreen email updates:



1 insulating paint posted by Brent Eubanks on 11/19/2012 at 04:17 pm

Am I reading this right: someone has actually produced an insulating paint that works?  It seems like this concept is one that keeps popping up, but is always revealed to be mostly or completely a non-performer (a less generous person might characterize those performance claims as fraudulent).  So if you've found something that actually works as advertised, that's worth talking about.

Any idea what performance characteristics the manufacturer is claiming?  Will you guys be investingating/testing this product in greater depth/

2 A coating that actually insulates? posted by Alex Wilson on 11/20/2012 at 12:04 am

Yes, I believe that this is a coating that actually provides some insulation value--unlike all the "NASA-tested radiant paints." With silica aerogel, a thin 2 mm layer should actually be able to make a difference, so I'm inclined to believe this. I felt the difference, and it was persuasive. That said, I look forward to seeing some actual third-party test results! We would like to follow up with a more in-depth product review.  -Alex


3 Love the cork but what makes it anti-microbial posted by TL Cornish on 11/20/2012 at 12:29 pm

Has anyone done a study to confirm that cork can discourage mold growth?

Despite my initial pleasure at these products popularity, I have had three experiences close to home that have me concerned for cork's future and for people's investments.

Though I would have recommended it in the past, my three closests contacts with it's use  have shattered my faith. After a friends cork floor, my own cork floor and a local yoga studio with it all developed mold growth, I'm deeply questioning the properties of it. Does anyone know why this might be happening and how it can be prevented in the healthiest, most ecological way?

All of these were concrete slab floors. One on top of poly and two bare.

T Cornish


4 What I suspect is this posted by Andy Parkinson on 11/20/2012 at 09:23 pm

With the moldy cork floor I suspect what is happening is that the concrete slab is cold and so condensation is causing moisture accumulation, leading to the mold.  Cork has good insulating properties and so insulates the slab from the heat in the rooms in question, if the concrete slab is uninsulated or thermal bridging is occuring the temperature of the slab will be below the dew point (assuming you are in a predominantly heating climate rather than cooling climate).  However, this is probably not a case of the material being at fault, but more how its used, and a lack of understanding of material properties and building science in material choice and application.   There are others, who have a much greater command of building science than I, who visit this blog so perhaps they will wade in and confirm my suspicions.  They (and I) will want to know your climate zone, and details of the building assemblies in question to make further analysis.  I like cork.

5 I WANT to like cork posted by TL Cornish on 11/20/2012 at 10:01 pm

Yes, I believe you are right though we had hoped that applying it without a vapour barrier would allow it to breathe enough to dry out. Many people do want to use it for warmer floors on slab and the company I bought from recommends it be applied with poly and says it is especially good for basements. Hmmm...They said the material was not at fault but offered no other installation recommendations. It's supposed to be anti-microbial so one would think that it would be a good choice for that application. If the floor had been insulated under the slab we'd have been fine but knowledge of that approach is only slowly growing. 

I think for now I'll like cork for second floor flooring applications and I'm a little hesitant about it in the wall envelope since there will be some similar potential there. 



6 T, this would be a great posted by Andy Parkinson on 11/20/2012 at 10:29 pm

T, this would be a great question for probably would get an interesting discussion going

7 valuable information. Thank posted by James Chambers on 05/03/2014 at 09:56 pm

valuable information. Thank you. I was poised to try this in a retrofit, but will wait for new construction, insulated below slab. Would be interesting to know if certain cork has better antimicrobial properties.

— Share This Posting!

Recent Discussions

posted by atwilson
on Feb 3, 2016

I believe the Viridian decking we installed is 15/16" thick by 2-1/2" wide; I'm not seeing those dimensions on the Viridian...

posted by Meredith_1
on Feb 3, 2016

Hi there! I've been sourcing reclaimed exterior deck material for a client, and am interested to know:

The thickness of the material you...

posted by tristan
on Jan 29, 2016

Erica, 3-way LED bulbs are sold in stores and online. Just do a search or ask at your local hardware store.

Recent Comments

Saving Wood from the Landfill, Without the Supply Issues

Alex Wilson says, "Meredith, I believe the Viridian decking we installed is 15/16" thick by 2-1/2" wide; I'm not seeing those dimensions on the Viridian website now,..." More...

Meredith Williams says, "Hi there! I've been sourcing reclaimed exterior deck material for a client, and am interested to know: The thickness of the material you used..." More...

Beat the Bulb "Ban": LED Replacement Lamps in a New Light

Tristan Roberts says, "Erica, 3-way LED bulbs are sold in stores and online. Just do a search or ask at your local hardware store." More...

Erica E. Tactical says, "Anyone know a way to replace incandescent 3-way light bulbs with LEDs? My table lamps are all 3-way and I like the ability to have ambient or..." More...

Autoclaved Aerated Concrete (AAC): Will the U.S. Ever Lighten Up?

Simon Hatton says, "Merhis Projects are an Australian Developer and Construction company and have been using their patented Merhis Building System for the last 4 years...." More...