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8 Answers

Insulating and protecting an existing brick wall

We are renovating our 100+ year old house room by room. We realize the most common and effective way to insulate is with spray foam (our brick is in excellent condition with no apparent water damage). Our problem is that because we are doing the renovations room by room, spray foam is not the most cost effective way to insulate. I can't seem to find any mention of using rigid insulation in previous articles. Can anyone make suggestions as to how to insulate with rigid (IE are vapour / air barriers required when insulating against the existing brick) and if it will do more harm than good?

In GBA Pro help | Asked By Amy Rancier | Feb 7 12
4 Answers

REScheck v. Energy Modeling

I'd like to start a discussion around the differences as well as the advantages/disadvantages of using REScheck (or COMcheck) and/or an energy model. Although REScheck seems to have been originally written to show energy code compliance cost-effectively, it is often used or mistaken for an energy model - I think primarily because it shows a "% improvement" over code, which is a commonly requested output from energy models when complying with a "above code" program.

I am curious to hear about people's experience using REScheck.

In General questions | Asked By David Epley | Feb 6 12
6 Answers

Best Practices in Mold-Resistant Bathrooms

GBA Community,
I have looked at a variety of best practices in mold-resistant bathroom strategies and materials for a moderate size full bathroom. I have landed on the following:

In Green building techniques | Asked By David Epley | Feb 2 12
0 Answers

An upcoming Passivhaus conference in Portland, Oregon

Passive House North West is planning a conference on Mach 2, 2012 at Portland State University’s University Place in Portland, Oregon.

The keynote speaker will be Jerry Yudelson. speaking on the topic “Climbing the Summit to Passive and Zero Energy Buildings.”

For more information, click here:

In PassivHaus | Asked By Martin Holladay | Feb 7 12
3 Answers

HRV Inlet Duct


I'm finishing my basement and discovered the HRV inlet duct insulation is damp at the bottom portion of the 90 deg inlet (pic attached).

Is there a better way to insulate this duct? During cold snaps here in the Pac Northwest, the rigid duct condensates, so last year, I wrapped it with insulation.

thank you

In Energy efficiency and durability | Asked By Frank O | Feb 7 12
5 Answers


I'm sorry I don't know how to get back to my original question. Air Krete's brochure says ALL GREEN INSULATION . The salesman said Retrofoam emitted gases. Retrofoams brochure says no fumes gases or emissions. Then I googled and it seemed that the words that came up said Air Krete that is made from...yes Retrofoam made by Polymaster. I guess what I want to know is IF Air Krete is made fro Retrofoam? And is Air Krete All Green? (I got asthma from black mold)

In Green products and materials | Asked By Connie Lambert | Feb 6 12
1 Answer

Second Try: Wolfgang Feist Responds to Rideau Residences Controversy

The Passivhaus Institut has approved the release of Dr. Wolfgang Feist's response to the controversy surrounding the Passivhaus certification issued to the Rideau Residences in Ottawa. (For more information on the controversy, see Is This Building Passivhaus-Certified?)

After GBA published Dr. Feist's response last Friday, the Passivhaus Institut told us that the release of the letter was not approved. Now we have heard that the letter can be made public. Dr. Feist wrote:

In PassivHaus | Asked By Martin Holladay | Feb 7 12
3 Answers

Dr. Wolfgang Feist responds to questions about the Rideau Residences

UPDATE: February 7, 2012. Dr. Feist's statement has been released. Click here to read it.

On February 3, 2012, Dr. Wolfgang Feist issued a written response to questions about the certification of the Rideau Residences.

After I received the statement and posted it here, I received an e-mail informing me that the Passivhaus Institut in Darmstadt is requesting that Dr. Feist's statement not be published.

I am respecting their request, and have therefore removed Dr. Feist's statement.

In PassivHaus | Asked By Martin Holladay | Feb 3 12
1 Answer

How to insulate including vapor barrier in building with metal siding

I am planning on building a home in zone 3A (Dallas) by first erecting a metal building and then framing the inside. Plan is to use R-panel for outside and then 2x4 walls. What is the best way to insulate this including what type and location of vapor barrier

In Energy efficiency and durability | Asked By Greg Trojacek | Feb 6 12
3 Answers

Temperature variation in bonus room over garage

Two-story home is located in Atlanta, Ga, and built in 1984. The house faces west. The bonus room over the garage has a separated roof from the main section of the house which make up most of the angle portion of the ceiling in the room. The roof has ridge venting.

The issue is continually battling temperature variations as I have tightened up the house with air-sealing.

In Energy efficiency and durability | Asked By Scott Razzino | Feb 5 12
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