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1 Answer

What mechanical system makes the most sense?

I am in a zone 4a Kansas City Missouri. In the heat of the summer it can get up to 95 with high humidity and it doesn't cool down at night.

We are building a 3500sqft ICF house with R-24 walls. (We have the labor and resources for it to be the most affordable option) and a R-60 SIP roof, cathedral ceiling. We are thinking about building with a 4' crawl space, unvented, 20 mil vapor barrier. Our windows and doors we are sourcing from company's in the U.S. which build to the PassivHaus standard.

I have a few questions:

Asked By Jordan Schiele | Sep 2 15
0 Answers

How to reduce the humidity in my home?

I live in a 1200 sq ft. mobile home and heat with electric space heaters. I do not tolerate forced air due to severe chemical sensitivities (it is propane), so all grills and ducts are blocked off. The humidity in my home runs between 40 - 50 % which is too high. I keep it closed up tight to keep out wood smoke and dryer sheets from the many close neighbors that I have. I am interested in the eGO for my laundry room, and wondering if the air coming in and out can be filtered with more than what it comes with. I am also open to other suggestions.

Asked By Suzanne Lippuner | Sep 1 15
1 Answer

Seeking advice on insulation and membranes for an exposed wood structural roof

I am working on a little house extension located in Toronto Canada. We are shooting for an exposed wood structure, with the insulation (required r-value 31) outboard of the roof's diaphragm which will either be tongue and groove or a very thick plywood.

I am very unclear on where my vapour barrier should be located - I was taught that the membrane needs to go on the warm side of your wood studs, in a conventionally framed wood house. In this scenario there is nothing below the warm side of my structure at the ceiling - there is analogy in the condition I am working on.

Asked By Guy Debord | Sep 1 15
1 Answer

Attic Insulation Upgrade

I'm struggling with getting the correct answer on how to proceed with upgrading my attic insulation.

I live in Pittsburgh PA climate Zone 5A.
My existing attic space has batt insulation on the floor with no air barrier and is vented at the gable ends.

I would like to spray foam on the underneath of the roof deck sheathing in-between the truss joists and on the gable end walls to meet the required R38.

I'm struggling to understand if I should use open cell foam or closed cell foam.

Asked By Forrest Watson | Sep 1 15
3 Answers

Roof ventilation ideas

I'm trying to add attic ventilation for my whole house fan, as the manufacturer states that I need a total of 4.4 sq. ft. of free air. I currently have gable vents, but they're located right above a window and the attic air gets sucked right back into the house (even when the window is closed, to some degree, and I'd like to open that window anyway). So I'm thinking of sealing off the gable vents and getting all the ventilation from the roof.

Asked By Robert Shelton | Aug 26 15
8 Answers

Why is there condensation on the return ducts and mold in the attic as well 60% humidity throughout the home?

This home has since been remodeled, including all new metal duct work and insulation. The issue that we need to resolve is the high humidity in the house at about 60-65% even though the unit is running efficiently. There is quite a bit of condensation on the return ducts in the attic as well. We have had two reputable Heating and Cooling Contractors come to assess the situation to no avail. The owner attempted to contact the original Mechanical contractor, but has not been able to speak to anyone yet.

Asked By Jimmy Miller | Sep 1 15
10 Answers

I am considering getting solar panels on my roof

I am considering getting solar panels on my roof and have quotes from 2 different companies. Is there anywhere I can go to get help on determining which are the better panels?

Asked By Dave Sanda | Aug 31 15
21 Answers

Skipping radiant floor heat in a passive house?

I'm building a house with (conservative numbers) R 60 walls and R90 ceiling. The windows are in-swing casements with double seals. The floor is going to be stained concrete on 2" insulation. I had 2 consultants tell me that I will not need radiant floor heat it will be too much. We will have a whole house air circulation system and a gas fire place. I am worried about not putting in the pipes in the floor and then being wrong. I am considering just putting in the heated floor under the rooms away from the fire place. I could add a heater to my whole house ventilation system if needed.

Asked By Jenz Yoder | Aug 25 15
2 Answers

Damp spray cellulose in Los Angeles

Does anyone have a recommendation for a damp spray cellulose installer in the Los Angeles area?

Also, out of curiousity what is the going rate in your neck of the woods for damp spray cellulose (2x6 wall)?

Thanks in advance

Asked By Jack G. | Nov 4 12
10 Answers

Comments on wall design, please

Attached is an image of a wall system I've conceptualized. It combines ease of interior electrical, plumbing, and wall finishing work with the structural benefits of CMU construction, the air tightness and performance benefits of a REMOTE wall, and the maintenance benefits of EIFS.

Looking for feedback. Any pitfalls with this approach? Overkill?

Thanks.

Asked By Matt Culik | Aug 31 15
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