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24 Answers

Best way to fix insulation problem in cathedral ceiling? Please help!

I built my chalet about 8 yrs ago and was up in the attic and noticed black water stains (probably mold).
after many days and night researching what was wrong, i believe my issue is insulation and air leakage.
i have called all the insulation and roofing businesses (not many in this area) and each says its the others issue.

this site has been the most informative, but i cant seem to find any article or videos on how to add or change insulation in a cathedral ceiling after construction has been done.

Asked By Aaron H | Jan 31 16
0 Answers

Proper DHP sizing

So, I ran a Manual J calculation for a number of Portland, OR apartment units I'm renovating (2bdrm/1ba, ~750sqft each). All fall in the 12.5k-13.5kbtu range for heat load; closer to 9-11.5k for cooling loads depending on orientation. When I click over to the Manual S sizing calculator, it mentions Emergency loads of 10k minimum - 18k maximum. I'm not sure what exactly this means, and how it should affect sizing choice. Calc outputs are attached for reference.

Asked By jonathan nagar | Feb 8 16
1 Answer

Best insulation for indoor air quality?

I cannot decide on a type of insulation for our new home. I want something that is the safest for indoor air quality. I am worried about the off gassing of spray foam, but am also worried about the borate used in blown in cellulose (mainly the reproductive effects of borate). Please help! I want energy efficiency, but indoor air quality is of primary concern. Thank you!

Asked By Carolyn Farrow | Feb 8 16
2 Answers

Wall assembly

If a 4 or 6'' wall works good, what is wrong with a 12'' version of it?

Asked By Michael Abrams | Feb 8 16
12 Answers

Geothermal and SDHV in new ICF home

We are in the process of building a new home in Climate Zone 5. It is an ICF [insulated concrete form] construction from basement foundation to gable.

I am intending to use a SDHV [small duct, high velocity] system for forced air and heating in conjunction with a closed loop ground source heat pump.

What I am trying to understand is the impact to efficiency caused by my desire for SDHV on the heat pump options side of life.

Asked By Esteban Carlos | Feb 4 16
4 Answers

Will this exterior wall system work for my tiny house?

I live in South Dakota in zone 6a (Sioux Falls). In a few months time I will be constructing a tiny house on wheels using 18 gauge structural studs. Starting in the wall cavity will be sprayed closed cell foam. On the exterior sides of the studs (and any other exposed metal areas- the steel trailer) I plan on using strips of 1 inch thick xps rigid foam with a compressive strength of 60 lbs/square inch. Also I will use steel strapping all around the outside to give it some shear strength and prevent racking.

Asked By Damon Beck | Feb 7 16
1 Answer

WooHoo!

I've been lurking here for awhile, doing what I could to make my home more efficient as money came in. As it was I've lowered my heating bills by about $850 a year before I started doing the more major stuff this year. Finally I had a home energy assessment performed, completed the suggested upgrades and then had the post retro-fit assessment completed just now.

ACH50 of 1.62 in an 11 year old house, and an EnerGuide rating of 85!

Asked By Calum Wilde | Feb 8 16
4 Answers

Raised-heel trusses can be annoying

We installed raised-heel trusses with bottom chord overhangs on our house. The top of the top chord is 20" above our top plate. According to the 2012 International Residential Code for seismic zones or zones designated for winds of 100 mph, raised heel trusses more than 15.25" have to be blocked and braced.

Asked By Jimmy Nguyen | Feb 6 16
3 Answers

Wall assembly

I am building a new home in zone 6. I have a question regarding insulation in the window wells. I have 4 inches of xps externally. Of course I do not have insulation inside the window well area. That leaves the header area and a small amount around the window uninsulated. Should I use an internal insulation in the stud bays around this area? One window well is in a bathroom. Should a smart membrane be installed in this area?

Asked By Charles Cloud | Feb 4 16
8 Answers

Trying to warm up an uninsulated concrete garage floor

Kenora Ontario Canada P9N0E7
Climate zone 7

Background- I have a 24 x 30 ft garage with 2x6 wood framed walls (R20 fiberglass batts in stud bays) and a raised heel truss attic (8 ft walls) the ceiling has R50 blown fiberglass.
The man door is located on the south wall and the two 7x9 insulated overhead doors are on the north wall...the ridge of the 6/12 pitched roof runs E-W.
The concrete pad is a 4 inch thickened edge slab over 6 inches of compacted stone; the earth is well drained and slopes away rapidly in all directions.
I use 1/2 the building for parking and 1/2 for a shop.

Asked By Tim Brown | Feb 7 16
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