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1 Answer

I am a paid member that can't access product guides

Now I have been blocked?

In GBA Pro help | Asked By Greg | Nov 26 15
2 Answers

How to separate house from garage

Our house will have 5" nail base on the roof with a 3" of oc foam on the underside and the walls will be ZipR over 2 x 6 wall. The garage will attached to the house. My question is do you build a wall in the attic between the garage and living area, then insulate it just like an outside wall? Also I don't want any pull down stairs in the house so what should I do for access to the attic from the garage? I thought about have an exterior door installed in the the previous mentioned wall.

In General questions | Asked By Eric Chandler | Nov 26 15
13 Answers

Ideal load for a multispeed inverter-driven GSHP?

In a planned "Pretty Good House" in Mixed Humid, Northern Climate Zone 4, I intend to use a 45 EER Ground Source Heat Pump with 3 inverters (loop pump, compressor, and fan) with a Cooling Capacity range from 9,000 - 24,000 Btu. I wish to have the lowest Peak Cooling Load, that utilizes the equipment most efficiently, while providing dehumidification and keeps short cycling to a minimum. Approximately what sould that theoretical Peak Cooling load be ?

In Mechanicals | Asked By Ted | Nov 19 15
3 Answers

Inward solar vapor drive with Zip R Sheathing

I am curious if Zip R sheathing would experience any issue with inward solar vapor drive.

We have an upcoming project that will use Zip R Sheathing (in the polyiso 1 1/2" variety) - and will also have a reservoir cladding - stone on the exterior. There will be a minimum 1/2" gap between the back of the stone and the zip - but it won't be ventilated. Still I was curious if the zip coating and osb might allow vapor to be driven through them only to condense at the outside of the polyiso.

In Energy efficiency and durability | Asked By Patrick Kelly-Decker | Nov 25 15
4 Answers

Mineral wool in an attic


This is a complete newbie question.

I read the article about Mineral Wool in Fine Homebuilding 254 (pp. 48-53 September 16, 2015) and it says that if you use it for insulating the floor of an unconditioned attic, you need to use a vapor barrier underneath it.

Would the painted drywall ceiling in the living space below the attic perform that function or do I need to install something in each rafter bay before putting in the mineral wool? Would that thin bubble-wrap-like insulation sheeting work?



In Energy efficiency and durability | Asked By George | Nov 25 15
2 Answers

Vinyl siding over rigid insulation

I have a multi family project that needs to be resided. Unfortunately we cannot afford to use cement board siding and are using vinyl. Is it possible to attach vinyl directly over rigid anchoring to the sheathing? It doesn't seem to be an acceptable attachment method from the vinyl siding manufacturers. Is it worth installing sheathing over the rigid, perhaps a taped zip system? Thanks.

In GBA Pro help | Asked By Julie | Nov 25 15
4 Answers

Builidng a house from the "Affordable Passive Solar Planbook for North Carolina"

I have the opportunity to possibly build a new house on a piece of farmland. I'm trying to keep the costs down, and I really want to incorporate ways to reduce build cost and future cost of heating the home. I'm in Calgary, Alberta.

In General questions | Asked By Solange Pomerleau | Nov 24 15
5 Answers

Exterior Roxul batt insulation in semi-conditioned space?

I'm building a 10x14 timber frame shed in upstate NY climate zone 5. It's under 144 sq.ft. so doesn't require building permits or inspection. I have pine 2x T&G roofing and 1x wall cladding from a local mill. The building will be used occasionally as a workshop, including during winter. For this reason I'd like to insulate it. I'm grumpy about foam for various reasons including rampant carpenter ants around my property and so would like to use rock wool.

In GBA Pro help | Asked By Michael | Nov 23 15
9 Answers

Spray foam and Roxul for flash and batt?

Hey guys,

I am in the process of finishing my attached garage in zone 5a. It will not be heated year round, just when I am working in there. When it will be heated, I will be using a 240v 6k watt electric heater.

I am torn on how to go about insulating my unvented cathedral roof. I ready that fiberglass batts against the sheathing are a no no but what about roxul? If that's no good either, can I just spray 2" of closed cell and fill with roxul then sheet rock?

In Energy efficiency and durability | Asked By Steve | Nov 23 15
48 Answers

Buyer education versus a good code and intensive enforcement of it

This is kind of a general question. I'm seeing more and more issues coming up on GBA questions and answers regarding shoddy construction that homeowners are having to deal with. I read it recently in Peter L's description of some builders in the Phoenix area. This is most concerning when one is having a new home built, or purchasing a previously built new home, and it has subpar construction.

In Building Code Questions | Asked By Eric Habegger | Jul 21 15
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