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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.

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?

Asked By Steve | Nov 23 15
3 Answers

Split system location

If I am going to install a mini-split in a very small, well sealed, well-insulated new home that will need airconditioning rarely (maybe never) but heat more often, does it make sense to install the interior unit at floor level instead of ceiling level? Is there generally an option offered by mfgr of low or high mounted units?

Asked By A Lange | Nov 24 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.

Asked By Eric Habegger | Jul 21 15
3 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.

Asked By Solange Pomerleau | Nov 24 15
1 Answer

At what temperature should blown foam insulation be installed on a steel roof with 2x6 trusses?

I have a 24x60 pole barn and want to keep moisture from dripping on inside items. It`s getting cold and I want to know at what temperature should blown foam insulation be installed? I`am more concerned with moisture than R value but plan on having 4 inches blown on the roof.

Asked By Gordon | Nov 24 15
2 Answers

Brick veneer air gap vents into rim joist in crawlspace/basement

50's rambler with a few additions over the years.
I believe it is cement board siding with brick veneer around the lower base.
Blower door test came in around 4,500 cfm50

Asked By B D | Nov 24 15
1 Answer

Solar array positioning in Charleston, SC

Our home builder positioned our solar arrays facing east and southeast, but the angle is pitched east on both. One bank of panels are partially blocked by a large oak tree to the east, the roof of the building to the south, and a 2 level garage which partially obstructs the array (12 in each bank) eastward. The other array is pitched east and catches a glimmer of southern exposure sun, but is partially blocked by other large live oak trees to the south,

Asked By F White | Nov 24 15
6 Answers

Does this setup seem sufficient?

After reading many of the articles and comments here, I've been inspired to try and build Passive House insulation and air tightness.

I'll share what I'm thinking so far with the hope that maybe you can direct me in any way. Not necessarily trying to get Passive House certified, but would like to build airtight anyway.

Region: west mountains of Dunlap, TN


Asked By Edwin Perdomo | Nov 23 15
12 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 ?

Asked By Ted | Nov 19 15
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