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3 Answers

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
10 Answers

Frost wall foundation details for stone and siding construction

I am planning a slab on grade build (24"X8" footings, 4' deep, with 4'6" frost walls). I am having issues with the location of all the sub components on the frost wall width, specifically on the stone detail wall (front wall only).

Asked By Mai Tai | Jun 18 17
4 Answers

Closed-cell spray foam and XPS: green or not?

I've posted several times on my pretty badly compromised attic. We live in a 50s ranch outside Chicago with a ceiling that has been butchered by can lights and an AC handler & ductwork. I feel the only reasonable solution is to move the conditioned envelope to the roof. I've debated and debated and debated this because the solutions are expensive, a pain to implement, and now it appears environmentally questionable.

Asked By Brian Gray | May 7 17
2 Answers

Is there a roof colour that is better for the environment overall?

We are building a house in Zone 4 just over the border in Canada. We are going with a single slab roof with a 2.5:12 pitch that angles to the east and will use metal as our roofing material. We thought we had read (somewhere, can't find it on the internet) that lighter coloured roof material can act like snow/ice and reflects sunlight back into space, therefore is better for the environment overall from a global warming perspective. Just wondering if there is any consensus out there in the GBA community on that.

Asked By user-6809777 | Jun 22 17
5 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

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
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