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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
8 Answers

Alternatives to recessed lighting in open floor plans?

The question is basic....

For those of you who have forgone recessed lighting in your home for air sealing and efficiency reasons, what did you use for alternative lighting?

My floor plan is very open (think 20' x 40 box), has relatively low ceilings, 8'9", and I want the area to remain flexible for future floor plan changes. There is no kitchen area, just a very small snack island that will feature a few pendants.

For all their issues, can lights are a nice option for providing even lighting across an open area without having fixtures dangling down from the ceiling.

In Interior design | Asked By Rick Van Handel | Sep 3 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
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