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1 Answer

Am I ok to lay down my plywood subfloor at 19% Moisture content?


I tested all of my 4x8 cdx plywood in the middle of the 5 sheets, and 2 pieces are at 19% moisture content (the rest are between 10-17%).

Should I go buy 2 new pieces or am I too concerned over the moisture content? I was reading that anything near the 20% range is way too high for plywood.

I purchased these 3 weeks ago and have been stacked in my shed. I did not test when I first purchased but I certainly would assume that they would be dryer.

Also, please see the pictures below. Does this look like water damage or mold? These are the two pieces that measured higher.

Asked By Grey wolf | Apr 27 17
2 Answers

Vented and Unvented Attic space

We are currently considering foam insulation during the framing phase.

Basically the trusses span over our patio area, approximately 15' with glulam at bird's mouth.

When looking at foam they will create a 'rake wall' with foam to enclose the attic from top plate to roof decking.

Do we need some sort of venting in this section of the attic (outdoor patio)? It will be an unconditioned space.

Asked By espy1 | Apr 27 17
1 Answer

Compact Re-roof, polyiso over spray foam?

Hello everyone!

I'm in the Lehigh Valley, Climate zone 5A (borderline 4A), and I have a roof that needs to be redone and insulated far more than it is now, it was originally a cold cellar back in the day, and is a relatively small area- 17' x 17'.

Asked By GreenStoneHome | Apr 27 17
6 Answers

Cape Cod attic — cellulose machine

My finished attic in my cape cod has terrible temperature regulation up here in central Maine. So far I've put 1 inch foam between the floor joists sealed the gap with foam. I've also spent days air ceiling the upper attic. Next step is for me to dense pack the sloped ceiling, which is made up of 2x8 rafters. I'll be using accuvent cathedral ceiling extensions to provide ventilation. The sloped ceiling is about 5.5 feet long so I'll be connecting two of the vents together and stapling at either side. The house is about 34 feet long and I have slopes on either side.

Asked By SciFiJock | Apr 25 17
2 Answers

Final unvented cathedral ceiling insulation questions

I posted in my previous thread about my roofline being problematic (which was pointed out quite often!);
PLEASE KEEP IN MIND THIS HOUSE IS ALREADY FRAMED! I cannot change the roofline unfortunately (had I known then what I know now)........with that in mind please see my questions below:

I have come to the conclusion that I need to do Closed Cell Spray Foam in the main areas where the roof is not a simple plane but interrupted with valleys, etc. (?)

Asked By User-6816910 | Apr 27 17
8 Answers

Is a single head minisplit practical?

This is a mostly accurate plan of dear, old Mom's house.
2265 ft²; zone 4 marine; target ACH50 = 1.5; 5000 HDD; 22°F design temp;
2x6 walls w/2 stud corners, 24" o.c., 1½" horizontal cross-hatched walls (similar to "Mooney"), 7" of dense pack cellulose; front wall faces north; awesome PV potential on south facing roof.

Asked By Mark Walker | Apr 27 17
3 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.

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.

Asked By NKoenig | Mar 26 17
1 Answer

Exterior wall installed on perimeter of OSB floor, yet rest of room is a cement slab?

Hi all.
We recently purchased a house and upon ripping the carpet out in one of the bedrooms noticed that the exterior wall has been built on top of an osb type floor, however directly adjacent is the cement slab. I've attached a picture.

I'm hoping that someone here may provide some insight into why the slab/osb combo has been used. The cement slab has heating put in the cement.

The house was built in 1998. It's considered a 'walkout'.
We are Alberta Canada. Thanks.

Asked By Frugalmumma | Apr 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.

Asked By Mark Walker | Apr 25 17
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