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0 Answers

Shop with Radiant Slab Heat - Do I Need Slab Insulation?


I'm planning to build a 40x96 shop with in-slab radiant heat. I will likely only heat to 55 degrees. I live in Central ND, zone 7a. Wondering if it's necessary to use foam under my slab. Any thoughts?

Asked By Adam Emter | May 29 17
3 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
11 Answers

Air Tight Garage Door?

I have a unique set of requirements for a garage I'm building. I've been unable to find anything online in terms of 7' x 7' air tight garage door.

1. Because of plumbing in the garage, I have to heat it all winter in an especially high altitude (cold) location in zone 7b.

2. The insulation is R-40 walls, R60 attic, R-20 around the foundation, with FPSF detailing.

3. I don't need to open the garage door more than about 10 times per year.

Asked By Kevin Dickson, MSME | Aug 30 13
1 Answer

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
4 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
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
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
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