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4 Answers

Airtight electrical boxes in masonry house?

Do I need to use airtight electrical boxes on a masonry/concrete house?

Cement plaster will be my interior airtight layer, but people are telling me that wall itself is airtight enough not to warrant the search for airtight electrical boxes.

In General questions | Asked By davor radman | Apr 27 17
10 Answers

Building a new home in Climate Zone 5 — Need insulation help

We are building a new home in zone 5 (Michigan) and I would like your recommendations on how you would insulate the walls and roof/attic space.

The home is 3500 sqft with 2750 on the main floor and 750 upstairs. The main living space (kitchen, dinning, living room) is open concept with a cathedral ceiling. Other areas have a more traditional attic space.

The basement will be unfinished and we will use 2" rigid foam under the slab and on the walls. (unless you tell me differently)

Walls are 2x6 construction.

In GBA Pro help | Asked By NKoenig | Mar 26 17
6 Answers

1974 construction retrofit

A friend is looking to replace siding and windows on his 1974 house in climate 4 marine. The main floor and upstairs walls are 2x4 and the basement walls are 2x6. There is timber framing inside that I suspect bridges to the ext sheathing w/o any insulation. Where he has removed some of the vinyl siding, he found fiberboard sheathing (R1.32 stamped on it). I don't know what is under that. (The garage is just studs + fiberboard + siding). The gable walls have 3" overhangs and the roofing is 2 years old.

In Energy efficiency and durability | Asked By Mark Walker | Apr 25 17
5 Answers

Manufactured foundation drains, e.g. Z-Drain

Our builder wants to install the foundation drain on top of the footer instead of alongside of it. We complained that this would potentially give us a line of standing water above the footer/foundation wall joint (though it would remain some inches below the basement slab level. ) We will have Tremco Tuff n Dri waterproofing all along the wall and along that joint, so if it does a perfect job indefinitely then we should be fine. But if not, we could get some wicking up that wall.

In Green building techniques | Asked By William Costello | Apr 26 17
2 Answers

Moisture control / insulation for new cinder block shop with loft / den.

Hello Folks

I've been reading through the forums for an answer to this question, but haven't been successful in finding one. I'm building for the first time, so this is a learning curve for me.

I live in west Florida, and have a project in the works. I'm going to be building a 55ft x 38ft workshop, that will be 2/3 work space, and the remaining 1/3 will be a loft / den living space with a small kitchen, laundry area, and bathroom. So around 1400sq ft. I am planning on controlling climate with a 3 air handler mini split system.

In General questions | Asked By brew0688 | Apr 24 17
1 Answer

Linseed oil paint--your experience wanted!

Through the years there have been a couple mentions of the stuff (Allback, Viking--old school linseed based paints) on the Q+A section here, but to date I haven't seen any candid reviews or recaps of folks' experience.

In Green products and materials | Asked By jonathan nagar | Apr 26 17
4 Answers

Tar Paper vs Red Rosin Paper

I'm having hard wood floors fixed and the contractor wants to use Tar Paper vs. Red Rosin Paper. Is one more health-safe than the other?

I'm very sensitive to smells and chemicals. We had Fiberlock put down on the subfloor that I was sensitive to. The contractor said the Tar Paper would serve as more of a vapor barrier to it, but i don't want to add more chemicals if Tar Paper is less safe than Red Rosin. Thanks!

In Green products and materials | Asked By Masb H | Apr 26 17
7 Answers

Deep blown in cellulose for attic - questions

I have a few questions regarding deep (beyond R60) blown in cellulose for an attic. Cellulose is relatively cheap and I'd like to maximise my attic insulation without causing any other issues:

1. Several manufacturers of cellulose insulation have depth/R-value charts that stop at R60. Is there any practical reason for this, or is it just because most people don't bother going above R60?

2. Does compression above a certain depth negatively affect the performance of the insulation in any way? I.E. does your R-value/$ go down appreciably beyond a certain depth?

In Energy efficiency and durability | Asked By Lance Peters | Apr 24 17
15 Answers

Raycore - is it the product for me?

I was pretty much on board with buying Raycore for the 4500 s.f. home I am building in downstate NY, which is steel framed, so I actually don't need any structural value out of the exterior walls other than for supporting the windows and doors (and supporting the walls themselves). I am also going with a wire lathe and stucco on the exterior - Raycore told me I could direct apply the wire lathe and did not have to use any sheathing if I did not need the shear strength, but I am hesitant to do so.

In Green products and materials | Asked By Joe McCarthy | Jul 14 14
1 Answer

Can rigid foam insulation be used on brick and mortar walls?

Hello, I am looking to finish my basement. I live in Chicago. 2/3 of the wall is poured concrete foundation. The top 1/ 3( which is mostly above grade) is brick and mortar. The brick and mortar section is also recessed from the face of the poured foundation by about 2in. I was orginally thinking of using ridgid foam but now after research I feel unsure about which type would best in my application. Any help would be greatly appreciated. Thank you , Steve

In Green products and materials | Asked By sburban | Apr 25 17
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