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5 Answers

Inherited a garage foundation. Should I retrofit?

Worcester Ma area - Dampish clay soil
Building will have an insulated concrete floor in time and likely heated.

What is there - I have seen the pics and site.
footings on 11/2" stone with foundation drains to daylight
10" poured concrete - 4' tall wall
not water proofed
4'' foam both interior and exterior, sits on footing, back filled with stone/sand gravel
3' wide plastic sheet goods over the top of foundation and foam
Plastic was draped and buried both sides with 11/2" stone
Sill seal
2x10 PT top plate bolted on.

Seems in great shape - seems a good design

Asked By Howard Kelley | Apr 27 15
1 Answer

Regarding site-built ventilation barriers

If one were to install with 2" rigid foam within the rafter bay then fill the remaining space of the rafter toward the interior of the living space with unfaced fiberglass insulation, would this work?

Then would it be possible to cover this with sheetrock or wood paneling? Thanks.

Asked By Brooks Bicknell | Apr 26 15
5 Answers

SIPs ridging

An acquaintance has a 5 year old SIPS house with visible ridging happening on the (unvented) roof. The builder (not me) went back and taped the seams. The question is whether there are other measures that the homeowner should do at this point, other than eventually adding ventilation to the roof? And does anyone have ideas as to what exactly causes the ridging?

Asked By Bob Irving | Apr 22 15
3 Answers

Do I need to use concrete screws for plywood over an insulated floor?

i am following your advice on using XPS on concrete basement floor followed by two layers of 1/2 inch plywood. My concrete floor is 15 yrs old will I have trouble with concrete screws in older concrete? Can I just fasten the second layer to the first layer of plywood or can I use adhesive on the first layer or do I need the concrete screws?

Asked By Rita Erskine | Apr 17 15
9 Answers

Window flashing for new construction

Good morning,
I am getting ready to install windows(aluminum clad) on my new construction and would appreciate help figuring out the flashing details.
The exterior walls are made of gigacrete wall panels. The panels are basically steel studs encased in 8" thick eps. The walls will get a coating of stuccomax(gigacrete'a proprietary exterior coating). There is 3" of eps on the outside of the studs so essentially the windows will be inset a little over 3".

I am attaching a few images so the wall components/window openings can be better understood.

Asked By asim majeed | Apr 6 15
5 Answers

How much of a 2 x 6 plate has to be on the stem wall?

The real question is whether to use 6 in or 8 in blocks for my stem wall. Stem wall is 24 in high, this is slab construction.

The wall is metal, membrane, 1.5 in ISO, 5/8 OSB, 6 in plate, 5/8 drywall, trim.

If I use a 6 in block and line the outside of the ISO with the outside of the block, that puts only about 3.5 in of the plate on the block. Will this work? The good part of this system is that the 3 in of styrene on the inside of the stem wall can be let untouched and thereby give me a good thermal break between the floor and the block.

Asked By Tooger Smith | Apr 16 15
5 Answers

Best HVAC options for large house in zone 5a.

I have a custom house with 3930 sq/ft of conditioned space in a development in northern Idaho, (Zone 5a). The basement is planned to be Logix Platinum ICFs with R-28, the main and upper floors planned as 2x6 advanced framing walls with cellulose, 7/16" OSB, Tamlyn Drainable Housewrap, 1.5" of Terrafoam EPS, and fiber cement siding.
I'm hoping to get the owner to agree to spray foam the attic sheeting to condition it (R-38 min.)
The basement is 1830 sq/ft including a conditioned space under a large garage. The upper two floors of living space are 1050 sq/ft each.

Asked By Nethaniel Ealy | Apr 15 15
4 Answers

WRB advice

Finishing several additions to a coastal home in South Georgia.
Basically...plywood, wrb, vented furring strips, cedar shingle sidewall.
Due to the hot summer we plan to go north for 4 months and won't be able to completely finish the exterior. Looks like the WRB applied is about as far as I can get.. So...what wrb to use.
I know these products have limited "uncover" time.
Thinking a liquid applied WRB might be the way to go...considering wind, ripping, etc.
Any thoughts......thanks

Asked By Robert Brown | Apr 15 15
5 Answers

What roof underlayment can be used on a non-vented metal roof?

I've put up a building that has a 14/12 pitch non vented roof but now the building inspection dept. is hassling me over using Titanium UDL30 underlayment under the metal roof. They say it doesn't breathe and can rot the roof sheathing. The ceiling is R49 with 4" of foam against the plywood sheathing followed by 8" of fiberglass and 2 layers of 5/8" firesheild drywall.

I'd like to know 2 things - are my building officials wrong and if they're not what type of underlayment is allowable under a hot metal roof? I'm in the midwest in zone 6a.

Asked By TeleTooler | Apr 11 15
1 Answer

Cape Cod Home - condensation on LL floors - mid-May through mid-September

Cape Cod Home - condensation on LL floors - mid may thru mid september... the basement is walk out with windows, slider, so a fair amount of air goes through.

I do understand the floor is colder than the air flow temp. The key piece of info is that there is no insulation under the concrete floor.

The real question.... can a layer of foam be put down over the concrete and then a sleeper floor over that ?? or simply the sleeper floor ? what is the correct way to mitigate that condensation problem on some level.

Asked By PrestigeProperties | Apr 13 15
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