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2 Answers

Whether it's worth removing Sheetrock in closets to spray foam

Dear all, I have a Cape Cod and plan on insulating the second floor by air sealing with 2 inches of spray foam and then finishing with 3.5 inches of Ultra Touch cotton batts to fill the 6 inch rafters.

There are a few closets that are sheetrocked and will take a great effort to remove. Since the closets have doors thus preventing most of warm air to condense against the roof after dense packing with cellulose should I have any concerns? Ideally I would like to air seal whole of second floor but ripping out all the Sheetrock is a large task.


In General questions | Asked By Michael H. | Jan 3 13
6 Answers

What is your opinion of using LOW-E reflective insulation for slab insulation?

I'm starting a home in South Eastern Wa. State. It will have a daylight basement. I was going to use for slab insulation LOW-E Reflective Insulation. Has anyone used that material before and what is your opinion?

The material is !/4 " foam foil.

In General questions | Asked By Dan Easton | Jan 1 13
3 Answers

HRV/Central Fan filtration

This question was inspired by the Q&A from Cathy who wanted to know about affordable alternatives to HRVs.
We recently bought a house with a bathroom fan unit we can set to run constantly or when humidity reaches a certain level. There's a separate fresh air intake on the side of the house that flows into the HVAC system, and the fresh air gets minimally filtered through the furnace air filter.

In Mechanicals | Asked By Reid Magney | Jan 2 13
2 Answers

Selecting correct windows

I am currently planning a new cabin at Shaver Lake California with elevation of about 5000 feet . The winter time low temp can get down to 10 degrees with Dec. and Jan. average low of about 21 degrees and daytime summer high average of about 87 degrees. My question is this. Should I consider triple pane windows with SHGC of 40 to 50 for winter time warmth?
I currently live in the San Joaquin Valley where we typically use windows with the lowest SHGC we can find and just accept whatever U-factor the specific window type and manufacturer provides.

Thank you
Gary Richardson

In Energy efficiency and durability | Asked By Gary Richardson | Jan 2 13
4 Answers

Questions on heating upper floor and controlling indoor humidity

We just bought a house in Seattle (2000 sq ft. 2 floors + basement) that has an integrated water/forced air heat ducted system on the main floors and basement and convectair wall heaters on the upper floors. We are looking at improving our energy efficiency and also controlling humidity issues we are having (in the 55-60% range on the 2nd floor and basement)

We just had an energy audit done and our contractor recommended the following:

- attic insulation and seal

In Energy efficiency and durability | Asked By Stephen Lim | Dec 31 12
4 Answers

Stone wool versus blown-in cellulose insulation in double wall assembly

I am designing a wall assembly for a home in a very cold climate Zone 7. Considering labor and material costs, what is the most cost effective insulation providing me with the highest thermal resistance? I like the fire resistance of Roxul stone wool batts and the idea that it's more DIY. How about the air transference between the two products? Thanks.

In Energy efficiency and durability | Asked By Matthew Michaud | Dec 30 12
1 Answer

Miscellaneous Insulation Questions

Hi all,

I posted my first question last night after months and months of reading. Now that I'm over that hurdle, I thought I'd ask a few more about a house I'm building for my family in CZ 4A.

In General questions | Asked By David Baca | Jan 1 13
4 Answers

If we use spray foam on the inside of our attic, should we also use rigid foam on the roof?

If we use spray foam on the inside of our attic, should we also use rigid foam on the roof? This is being built in Upper MI.

We had an estimate for spray foam and along with spray foam. The company states it would then put 1" rigid foam on the outside of the roof. Is this normal practice, as I thought you insulate one side, not both? It is an A-frame with cathedral ceilings.

Must be vented by code, insulated to r-49 on roof, R21 in walls. spray foam was to 39 with 1 inch rigid foam on exterior roof. We are planning on putting 4 inches of rigid foam on outside walls.

In General questions | Asked By gary mccaslin | Jan 1 13
4 Answers

Open Cell roof deck or attic floor

Done my research, open cell foam is my preferred choice. Building a 3,300 sf house in Fort Worth TX. Pitch of roof is steep 12@12. House is single story. Considering the following two foam options, would appreciate feedback. Additional info, going with two a/c units (4 and 2 ton, both units are two stage. Also using erv air exchange to supply fresh air.

In Energy efficiency and durability | Asked By Jeff Bailey | Dec 29 12
2 Answers

Using a heater to raise the bathroom air temperature: a moisture question

In my home I use a small, electric kickspace heater to raise the temperature in the bathroom during showering. The elevated air temperature allows for the air to hold more of the moisture and raises the window glass temperature, reducing condensation on that glass.

In General questions | Asked By todd Stanley | Dec 31 12
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