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16 Answers

Interior impenetrable membrane for SIP roof and floor panels

I'm in the detailing stage of my cabin and need some advice on air/moisture sealing of the SIP panels. The panels (12 1/4" from Insulspan) willform shed roofs and the main floor only (the walls are 2x6's with Roxul Comfortbatt insulation, interior Membrane barrier with 1/2" drywall, exterior 1/2" plywood sheathing, Stoguard, 2" Roxul Comfortboard, 1 x 4 furring and then LP Smartside cladding). Inside the cabin there will be an 8" deep false floor built within the exterior walls to run plumbing and electrical.

Asked By Scott Wilson | Jun 5 17
20 Answers

Retrofit single ductless minisplit to cool entire upstairs

Hello, I'm a huge fan of this website, but I finally joined so that I could ask this specific question:

My wife and I own a 2000 sq-ft colonial built in 1962 in the Metro Detroit area (climate zone 5), with only baseboard heating--no central air. The first floor can be kept comfortable with a single wall-mounted AC unit and some fans to help circulate, but the upstairs is a bigger challenge. We've had several options quoted to provide some form of AC, but we're leaning strongly towards a ductless minisplit system.

Asked By Nathan Efrusy | May 9 17
9 Answers

Housewrap under rigid foam AND taped rigid foam at windows

the set up: Climate Zone 3. I'm using a standard house wrap between the OSB sheathing and the 1" rigid foam. The rigid foam will have all seams taped and will act as the primary WRB behind 3/4" vertical furring and lap siding. The Question : How do I terminate the house wrap at windows? just bring all the way into the "outtie" window bucks (caulk to buck), install rigid foam, then install window peel and stick flashing on bottom/part way up the sides. Install window. Would you recommend a 2nd layer of house wrap around the windows? Attached to the rigid foam?

Asked By Inger Peters | Apr 17 17
17 Answers


Hey everyone, I'm new here, so please bare with me if I missed something.

After reading this forum for a little while, I'm convinced that doing things right (particularly insulating) is not a question anymore. Me and my fiance just bought our first house (Northern NJ) and need to replace the roof. We got a couple of quotes from the local guys, but most did not react too well when I asked about insulating the roof. GAF does not recommend it, or it is not necessary (one guy said R25 value in the attic is plenty for our area).

Asked By Eldarchik | Jun 14 17
4 Answers

Add on demand to boiler system

We have a baseboard hot water boiler that is also used to heat our DHW(built in 1988). Seems we have larger than average gas bills even in summer. I have noticed that the boiler comes on even after 1 shower.
I am not sure if the temp set points are too low, boiler needs inspection, or to eliminate the side arm from boiler to DHW( Then add an on demand water heater). Bill over $100 mth seem very high for 2 people.

Asked By Bill Skaff | Jun 15 17
16 Answers

Blending energy efficiency with attractive design: “Boxy But Beautiful”

Is there a good source of images or ideas for Passive, Net-Zero or Pretty-Good Houses that have managed to strike a balance between sound energy efficiency and an attractive exterior design?

Some GBA articles have wrestled with this:

Banish These Details From Your Plans

Martin's Ten Rules of Roof Design

How Many Green Building Principles Are There?

Origami-Inspired Homes

Bronwyn Barry talks about "Boxy But Beautiful."

Asked By Pat Kiernan | Jun 12 17
4 Answers

Why am I supposed to seal ventilation baffles?

One reason for venting a roof (in addition to keeping the sheathing cold) is to release moisture from the attic. Given that (and assuming it is a given) I'm a bit unclear on the benefit of air-sealing ventilation baffles, particularly in a cathedral ceiling application where the baffles are continuous from soffit to ridge.

Asked By Christopher Wegscheid | Jun 15 17
4 Answers

Adding exterior insulation to 100 yr old house - added risk for rot where framing contacts foundation?

Going to add exterior insulation (spray foam likely) over 1 layer of siding. The house has a rubble foundation with no capillary break between the foundation and the framing. The ends of the floor joists are embedded in the foundation.

The house had 2 layers of siding. I've removed the outer layer to expose the inner and found the inner siding and sheathing rotted at the bottom of the wall where it covered the band joist and sill. See pictures. Luckily, the joist itself is in good shape.

Asked By TIM LANGE | Jun 14 17
4 Answers

How do I seal the slab edge in my basement around Stego Wrap and foam?

My basement slab has been poured, and I'm ready to cut back the Stego Wrap and 1/2" foam at the perimeter of the slab.

Is there a durable, low VOC sealant that would be ideal for filling the gap between the Stego Wrap and basement wall?

After this edge is sealed, is there a good way to dress this area up? Is there a specific kind of moulding that would nicely cover this slab/wall connection without taking up too much space? The only finish on the concrete walls will be primer and paint, no drywall, and for the floor probably only a sealer.

Asked By Eric Whetzel | Jun 13 17
3 Answers

Sub Basement Crawl Space

In the planning stage for steep slope home in North Carolina. After the topo survey results came in today, it is obvious we will need a crawl space under the lower level(will have main floor, lower level, then crawl space below due to steepness of lot). The foundation will step down on the sides. The way the builder describes it, they generally leave dirt floors, then encapsulate and condition this space and spray foam the walls. Seems to me I would rather treat this crawl like a mini-basement.

Asked By Kevin Spellman | Jun 14 17
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