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2 Answers

Blower door question

I'm going to have a blower door test done eventually. Do they have a cheap, repeatable way to block flapper dampers, used to provide makeup air for bathroom fans and a whole house fan during an blower door tests? My house is a bit experimental in using several large ones for the a whole house fan. They will have custom insulated plugs that block them off in winter, so this is more of a general question and not for my house specifically.

In General questions | Asked By Eric Habegger | Apr 27 15
8 Answers

Insulating a Quonset hut - (Can we make a sandwich?)

Imagine an arched metal Quonset hut, such as an older aircraft hanger. The skin of the building is structural; there is no structure under. The buildings are a set of panels which are bolted together, weatherstripped to form an arch. Each arch is bolted to the next to form the building.

Many of these structures are used a workshops or garages, we would like to use one as a studio. Typically these are insulated using either spray foam or fiberglass that is pinned to the shell, which looks somewhat like a quilt.

In Green building techniques | Asked By Doug Reid | May 4 12
5 Answers

Improve efficiency and comfort of this room?

Please see the 2 attached pictures of a room that I would like to improve the efficiency of. The room is between the garage and the main house. I don't like coming in from the January cold only to be greeted by a cold room. I dislike paying the oil man even more that.

In Energy efficiency and durability | Asked By Michael Lee | Apr 22 15
5 Answers

How does foil facing on attic side of roof sheathing reduce attic heat gain?

I thought that in order for foil surfaces to reflect heat, they need an air space 3/4" - 1" and that the foil must face the source of heat (in this case - outside)

In Energy efficiency and durability | Asked By Aaron Becker | Apr 26 15
2 Answers

Using SIPs for my upcoming roof project

I have a 4'x 12"pitch 50 square ranch roof. Open interior rafters and existing T&G decking above rafters. I will be installing a metal roof over and am interested in a R50 SIP as insulation above the T&G board decking. I need to know the best way to seal the exterior (top) of the T&G boards, and then how to seal both the underside and top of the SIP Panels. I also need your suggestions on venting continuous soffit to ridge plenum. Perhaps a "Cold Roof" above the SIP panels and below the metal roofing?

In General questions | Asked By Donald Harvey | Apr 26 15
1 Answer

Regarding site-built ventilation barriers

If one were to install with 2" rigid foam within the rafter bay then fill the remaining space of the rafter toward the interior of the living space with unfaced fiberglass insulation, would this work?

Then would it be possible to cover this with sheetrock or wood paneling? Thanks.

In GBA Pro help | Asked By Brooks Bicknell | Apr 26 15
3 Answers

Sizing an HRV unit

Hello, community,

I am renovating my 1903 2 1/2 story colonial house in southern connecticut, zone 5a. The house is listed as 2,100 sq ft (ground floor + 2nd floor), but I am also finishing and including the attic into the building envelope, giving an additional 1,050 sq. ft. for a total of 3,150 sq. ft. of conditioned space. I will be using closed cell spray foam insulation in all walls and roof. Heating is hydro air, and cooling is central air. System is split on 2 units, one for 1st floor and one for the 2nd floor and attic.

In Mechanicals | Asked By gary bruzzese | Apr 26 15
8 Answers

Water heater standby losses

Does anyone have a reference for the standby losses (in BTU/hr) for a "typical" gas-fired 40 gallon water heater?


In Mechanicals | Asked By Pete Engle | Apr 28 10
1 Answer

Seal (without insulating) rim joist?


I've got a crawlspace in a 1940 home that is reasonably warm and dry, but I want to seal against airflow and spiders. Is it crazy not to insulate as well?

I feel like I can get the sealing done now, and might insulate at a later date.

If I go this route, what is best for sealing the sill plate and rim joist (not sure if I'm using those words right...)? Caulk only, or Great Stuff? If I use Great Stuff I imagine the process being easier -- it's a tight crawlspace -- but I'm not sure if that works as well.

In Energy efficiency and durability | Asked By Firsty Lasty | Apr 25 15
2 Answers

Passive Solar: is a tweak to increase orientation towards the south worth it?


Bald eagles and osprey are busy snatching fish from the lake. Migrating pelicans and loons are stopping by to feed. And we our readying for our May 15 passive solar cabin groundbreaking at 46 degrees N in Minnesota.

We are razing an old 500 sq ft cabin to make way for our 1,100 sq ft cabin that folks on this forum vetted previously regarding heat pump sizing. http://www.greenbuildingadvisor.com/blogs/dept/qa-spotlight/designing-hv...

In General questions | Asked By Randy Bunney | Apr 24 15
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