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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)

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?

Asked By Donald Harvey | Apr 26 15
47 Answers

Installed R-60 insulation in attic... now using AC more than before

I had R60 blown into my 1000sqft attic where there was previously only about R11. Baffles were installed in almost every roof rafter. Air sealing of attic floor was performed. This is a low pitch asphalt shingled hip roof over the whole house.

Asked By Jeff Watson | Jul 12 14
7 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.

Asked By Doug Reid | May 4 12
5 Answers

Inherited a garage foundation. Should I retrofit?

Worcester Ma area - Dampish clay soil
Building will have an insulated concrete floor in time and likely heated.

What is there - I have seen the pics and site.
footings on 11/2" stone with foundation drains to daylight
10" poured concrete - 4' tall wall
not water proofed
4'' foam both interior and exterior, sits on footing, back filled with stone/sand gravel
3' wide plastic sheet goods over the top of foundation and foam
Plastic was draped and buried both sides with 11/2" stone
Sill seal
2x10 PT top plate bolted on.

Seems in great shape - seems a good design

Asked By Howard Kelley | Apr 27 15
15 Answers

Deep energy retrofit — Envelope upgrade questions

We are well into the process of a deep energy retrofit for our 2,700 sq. ft. house in NYC suburbs, zone 4/5A. The house is a typical 1988 contemporary with 2x6" wood frame construction, builder grade, sloppy subs, code minimum and 25 years of neglect. Long story short, we are currently replacing the roof, windows, doors, siding and HVAC. Before we started renovations, the blower door test result of just under 11 ACH50, proved that the envelope could be improved, so that is now our focus.

Asked By Andrew Wuench | Mar 31 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.

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.

Asked By gary bruzzese | Apr 26 15
5 Answers

Suggestion for making a 30 year old home more efficient while roof and siding are off

We live in Columbus, Ohio and have a home built in 1986 with the following floors. Floorplans and photo are attached as an FYI.
- Basement: 740sf finished, 250sf crawl space
- 1st floor: 1000sf
- 2nd floor: 800sf

Asked By Chad B | Apr 25 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?


Asked By Pete Engle | Apr 28 10
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