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6 Answers

Do Light-colored 'cool' Roofs add to winter heat load?

Has anyone done a calc to compare the summer savings from a cool roof versus a possible greater heat load in winter than that where the roof is dark-colored?

Asked By David Goldman | May 27 17
2 Answers

Should I tape vapor barrier to foam board?

Good day. I'm remodeling a tub surround on an exterior wall and want to air seal properly. Should I tape closed the "pockets" of black plastic, which I believe are the laps of vapor barrier where they come through the foam board and then down on the outside?

Tim in TX

Asked By TX Tim | May 28 17
6 Answers

Hot dormer: radiant barrier time?

I have read Martin's "Radiant Barriers: A Solution in Search of a Problem"

I have an existing house, about two years old. The second story is made up of two dormers, a bathroom, a "bonus room," and some "usable" attic space (outside building envelope).

The second story gets much hotter than downstairs (8-10 degrees in hot days). I'm interested in whether there's anything we can do to address that, short of cranking the hvac.

Asked By Maurice A | May 27 17
3 Answers

Wide door for workshop built to passive house standards

I am looking for an affordable wide door for a workshop that meets passive house standards.

I want to preserve as much wall space as possible.

I am looking for at least 6 to 8 feet of opening. With this being a workshop, it doesn't need to be a work of art, just functional.

I had looked at the Zola breezeway panel door. That is not available in their lower priced uPVC lines.



Asked By Andrew Sanderson | May 28 17
0 Answers

questionnaire about the thirty years old panel

Sorry that my question was not clear enough, and thank you a lot for the help I appreciate it . we have some of those panels in my university that I’m applying my project on. We were looking for the data sheet for them , however, ours were the same as the panel in the picture but not the same nameplate , the nameplate was not clear to read and I think they were not silicon. (No. LG250-12) by the solar power corporation SPC. Are they the same?.

Asked By shrik kader | May 29 17
0 Answers

20 minute fire door for passive house?

Does anyone know of a 20 minute fire door that meets passive house standards?


Asked By Andrew Sanderson | May 29 17
1 Answer

Martin - Knee wall and foam

Martin, I recently asked question about air washing insulation in knee wall applications and you suggested foam backing and said it would not create a double moisture barrier. (can't seem to add a follow-up question to the thread) I have since read several other posts on this site which suggested that foil faced foam in this application would create a moisture trap. Please clarify.

Asked By Bob Brown | May 28 17
2 Answers

Best solution for high humidity retrofit

Anyone heard of Lunos E2 units being used in a retrofit with high humidity in Ontario? Or has anyone used a Lunos Nexxt system? My Rep assessment said I needed to bring in about 53 com fresh air, so I would need 2 of the E2 series making 4 holes in the wall without addressing basement humidity. I live in a 980 sf bungalow end unit and humidity is often 55 , winter or spring. Two days ago it was 61. Mould starts to grow on the glass door edging. The furnace is about 15vyears old and does not bring in fresh air. I'm not sure an Hrv makes sense since the place is so small.

Asked By cdbh12 | May 28 17
19 Answers

How important is a thermal break between a house foundation and an attached garage foundation?

Our footings were poured today for a new house and attached garage. The walls of the basement foundation (9') and garage foundation are scheduled to be poured next week.

Looking over the plans, our concrete sub is worried about the 7" thermal break between the basement and garage foundations (no physical connection) as currently drawn on the plans. The separation is there in order to allow us to attach 5" of Roxul Comfortboard 80 to the basement foundation (we'll be doing the same for the whole exterior perimeter of the basement foundation).

Asked By Eric Whetzel | Dec 2 16
1 Answer

What is the best flooring for pier and beam with plywood subfloor?

I have a house on pier and beam with a plywood subfloor. The cavities between floor joists are filled with about 4-5 inches of open cell foam. I live about 50 miles southeast of San Antonio, TX. I need suggestions for flooring that will allow inward drying of the subfloor. Thank you in advance for you help/suggestions.

Asked By Brian Hons | May 28 17
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