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4 Answers

Rigid insulation beneath floor on shed


First time posting and would like to thank you in advance for at least taking the time to read this.

I am building an insulated shed/writing studio for my wife. Looking to make it 12'x8' and was thinking of building it on concrete blocks with 2"x6" studs for the bottom frame. On top of that I was planning on 2" rigid insulation followed by plywood then flooring. Will I be able to put the sill plate on top of this and drill through to the 2"x6"'s? I haven't worked with rigid in this context before.

Putting it on blocks seems the best option in case we wish to move it later.

Asked By Allan Manley | Jun 22 17
2 Answers

Electrical and plumbing clutter alongside foundation sill

I have been working out the details of how I go about insulating my pour concrete interior basement walls. I have researched the options and read a ton of discussion on many web sites. I have basically decided to apply EPS rigid foam board directly to the concrete and then a stud wall filled with mineral wool and covered with sheetrock.

Asked By David Pantalone | Jun 21 17
2 Answers

Looking for a cost-effective, “traditionally styled” double-hung window with U-factor of about 0.20

I am building a new house in Hopkinton, NH. (on the border of climate zone 5A & 6A) and am looking for a double hung window with a u-factor of .20 (or better of course) that will look good in a New England farm house styled home. What I mean by this is I would like a clad exterior with a wood interior and SDL grills without having to spend $65,000 on a triple glazed loewen or marvin window. Don't get me wrong I have used both brands of window on customers houses and they are beautiful, but they are not in the budget for my own house.

Asked By Eric Marchand | Jun 22 17
1 Answer

Which ductless minisplit?

Zone 4 climate - 735 sqft - R25 walls - R40 roof - R5 windows - very tight ICF home - glazing is minimal with a low SHGC

A Manual J was done and it showed a 1 ton unit would heat/cool the home. I'm undecided if I should bump up to a 1.5 ton unit? Here are my options:

A - DuctlessAire Mini-Split - 1.5 ton - 21.0 SEER - $1,400
B - DuctlessAire Mini-Split - 1 ton - 21.5 SEER $1,060

Is it worth the extra $340 to up-size to the 1.5 ton unit?

Asked By Peter L | Jun 22 17
1 Answer

Fastening foil-faced polyiso under floor joists

Martin advised, "My favorite specifications for exposed floors like yours: Install a continuous layer of rigid foam on the underside of the joists -- foil-faced polyiso is the easiest type of foam to tape -- and blow cellulose between the joists." (http://www.greenbuildingadvisor.com/community/forum/energy-efficiency-an...)

Asked By Mark Walker | Jun 21 17
4 Answers

Basement slab insulation

Building a cabin in Montana (climate zone 6) which will have an unfinished "basement" functioning as a mechanical room containing electrical panel, water cistern, pump, pressure tank, storage, etc. Code requires footings be minimum of 48" deep so I'l probably make them a little deeper and start my foundation wall at 5' of depth to gain a little headroom in the basement area.

Asked By David Williams | Jun 21 17
7 Answers

Are gaps in double top plates an issue for airsealing?

Hello, I have a gap in my double top plate (see picture). Is this okay for an airtight approach? I plan to tape my plywood sheathing.

Should I just fill this gap with insulation or fit in another piece of wood?

Asked By Rocky12 | Jun 20 17
10 Answers

Completely insulate / cover a window in an open cell foamed attic?

You guys answered a lot of questions for me last year during my retrofit of open cell foam in the cathedral attic of a 20 year old home I bought. For the most part, things are great, but the dehumidifier that I have in the attic still seems to have to work way too often to keep the humidity around 50% even though I also have a couple of registers cut inline on the supply trunks up there as well.

Asked By John Sexton | Jun 20 17
23 Answers

Exterior foam and fires

There has been a fire that gutted a high rise apartment building in London. It appears to have spread through the foam-filled exterior cladding panels. Similar fires have occurred in tall buildings in Dubai.

While the situations aren't directly analogous, I wonder if there are any lesson here for builders contemplating the use of exterior foam?


Asked By Malcolm Taylor | Jun 14 17
24 Answers

Sealing bottom plate to slab

My framer says that Sill Seal does not do a good job. I am inclined to agree with him. He is recommending a bead of liquid nails. I have been looking for real information. Certainly by now there have been some test run to measure the efficacy of various products and methods. And a new home slab is not a laboratory. How well does this or another product stick to a slab that has been wet and muddy?

Asked By Hugh Stearns | Aug 28 13
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