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7 Answers

Mold Growth on Tremco Enviro-Dri (WRB) Walls

Could really use some help from the experts here on the next recommended steps to take to find a solution to the mold growth in my basement. I have a one year old home in Tennessee that was built using Tremco Enviro-Dri and Tuff & Dri products. About 2 months ago, I pulled back the insulation to began to run electric in the basement and found the sheathing and insulation to be damp and mold starting to grow. It appears to be a condensation problem as it was fairly universal across all the exposed framed basement walls, but is worse on the north facing walls.

In General questions | Asked By Chip Keim | Feb 27 12
4 Answers

Double stud wall

Getting ready to build my own home. Looking at a wall assembly of 2" exterior EPS, plywood, 2x6 exterior wall with r22 fibreglass batts, 6 mil poly vapour barrier, 2x4 interior with r14 fiber glass batts and 1/2" drywall. I maintain r30 to the exterior side of the vapour barrier and r14 on the interior side so the 2/3 - 1/3 rule is maintained. I will not have to be concerned with electrical box and plumbing penetrations through the vapour except for items venting or take air from exterior.

In Energy efficiency and durability | Asked By Sheldon Lee | Aug 24 14
15 Answers

Open-cell spray foam in joist areas with polyiso on exterior walls?

From all the reading I have done, am I correct that I don't want to use closed-cell and need to use open-cell spray foam in the band areas of floor joists of the basement to 1st and 1st to 2nd floor areas when I have used polyiso sheathing on the outside of the walls?

I believe that is correct because of the perm is so low for the polyiso and you don't want to use another very low-perm product like closed-cell spray foam sandwiching the Zip wall sheathing. I'm just confirming if I read everything correctly.

In Energy efficiency and durability | Asked By john bell | Sep 19 12
2 Answers

I have a slab on grade, no insulation that I want to insulate and include a vapor barrier in zone 5B. What is the best way?

This is for a summer cabin and I would like to reduce the humidity in the cabin and also reduce air conditioning costs.

In General questions | Asked By Joseph LeBeau | Sep 3 14
9 Answers

Garage wall insulation

26x40 attached garage with radiant floor heat in the slab. Standard exterior construction, i.e. 2x6 walls, sheathing and Tyvek with vinyl siding.

I am trying to plan the most effective way to keep my radiant heat in the garage so it can stay warm and help warm the bonus room above. I have several ways of doing this and would like an opinion on them:

1. Spray 2-3 inches of open cell foam into the stud cavities, then drywall.

2. Spray 2-3 inches of CLOSED CELL foam in the studs and drywall.

In Energy efficiency and durability | Asked By Anthony Hughes | Sep 4 14
4 Answers

Is it possible that using a solar-powered attic fan would be appropriate in my situation?

Is it possible that using a solar-powered attic fan would be appropriate in my situation? Would using "Reflectix BP24025 24-Inch by 25-Feet Bubble Pack" be a good choice?

I am a southern Californian living in a home built in 1955 facing an AC and Ducting Nightmare.

I read MARTIN HOLLADAY article posted oct 26 2012.... Musings of an Energy Nerd
Title: "Fans in the Attic: Do They Help or Do They Hurt?"
"Homeowners in hot climates need to understand the difference between whole-house fans and powered attic ventilators"

In Energy efficiency and durability | Asked By John Alberti | Sep 4 14
1 Answer

How would you insulate cathedral ceilings?

How would you insulate your cathedral ceilings? Rafts are 10-12 inches deep.

if you have your house insulated, how do you like it? What would you have done differently?

I had a guy over to bid on sealing and insulating the cathedral ceilings with foam spray. He suggested I go with dense blown-in fiber glass instead because it works better. I had to ask him how long he's been in business. 7 years.

I don't know what I'm missing here.

Any tips on finding contractors I can count on getting the job done right?

In General questions | Asked By Jesse James | Sep 4 14
8 Answers

Cathedral ceiling retrofit

I have a section of my house with a cathedral ceiling.

SW Michigan - Zone 5A
~50 lb snow load area
4/12 pitch.
One side of the cathedral runs up to the house.

The current ceiling is (from inside the outside):

Roof is 17' wide and 20' run, gutter to ridge.
Timber Rafters - ~6' on center, about 4'x10'
T&G boards on top of the rafters.
About R-20 (guessing it is 6-8" thick) insulation.
Roof deck and black asphalt shingles.

I have 2 problems.

Bad ice dams
Noticeable temperature change to the next room. (hotter in summer and colder in winter).

In General questions | Asked By Ian Osborn | Sep 2 14
24 Answers

Solar panels for electricity generation

I would like to decide on putting in solar panels to reduce energy costs.

I have read about the next generation solar panels not being to far off.

Question: Would it be better to install current solar panels or wait for the new type that will be coming shortly?

In Green products and materials | Asked By John Alberti | Aug 26 14
0 Answers

I am considering using Boral TruExterior trim on a new house in lieu of Azek board

I am considering using Boral TruExterior trim on a new house in lieu of Azek board. I have been told that the product offers equivalent performance for less money.

Anybody have any opinions regarding this product?

In Green products and materials | Asked By Chuck Plaisted | Sep 3 14
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