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1 Answer

Building a new house, looking for opinion on insulation/exterior foam combinations

I am currently in the process of designing a new home. I built one four years ago that we have decided is too big and inefficient for what we need. This time around I am looking to build small, simple and efficient. The house will most likely be framed with 2x6 walls, however I would like to maximize R value of that wall.

Asked By user-6801629 | Mar 23 17
0 Answers

Replacement boiler sizing based on past usage

I'm looking for some reassurance and validation before I pull the trigger on an expensive purchase.

I currently have a 40+ year old, 137,000 BTUh oil boiler that is getting long in the tooth due to substantial corrosion. I have done many efficiency upgrades to my home. I am very interested in replacing the boiler with an electric boiler as the boiler I have now short cycles since I have improved the efficiency of the home so much.

Asked By Efficiency Fan | Mar 23 17
4 Answers

Insulating floor of an old barn

I have an 1804 bank barn and plan to use the lower level as a shop. Since dirt falls through the floorboards above anytime I walk upstairs, I need to think about insulating as a first step.

The easy thing would be to spray open-cell foam on the ceiling (bottom of 1.5" floorboards); but, I'm concerned that the foam won't maintain an air seal when people and machinery move around upstairs.

Asked By Michael Stelts | Mar 22 17
3 Answers

FPSF: Wing insulation with sub-slab insulation


For a frost protected shallow foundation, I was wondering whether folks who use sub-slab insulation also like to include wing insulation? Code doesn't require both.

I would expect that the wing insulation raises the temperature of the soil under the edge of the slab toward the deep soil temperature. This ought to have an impact on energy loss through the bottom of the slab, but is it significant?

Are there any studies that show the thermal gradient under an insulated slab, and how it's affected by the addition of wing insulation?


Asked By John Ranson | Mar 23 17
8 Answers

Material for preventing thermal bridging at steel beams and columns?

I have seen drawings showing an insert at the base of steel columns and where a steel beam bears on the top an exterior concrete stem wall (or in a beam pocket) that is intended to reduce thermal bridging at those points.

Does anyone know where to get this sort of material? A local structural engineer mentioned a carbon-fiber product that is quite expensive. He didn't think it would be worth the bother and expense. Anchor bolts (2 to 4) at each point will bypass the thermal break material.

Asked By Pat Kiernan | Mar 17 17
1 Answer

Insulation of mobile home

We are renovating a 1976 single wide trailer. We have removed all the interior wall and ceiling panels. Currently the walls have the pre-existing pink fiberglass insulation and the aluminum siding, on the ceiling there is the same insulation and then plastic sheeting. We would like to add additional insulation before we drywall. We have looked into double bubble foil insulation, but then read an article on here as to why that would not be advised. What is the best product to provide more insulation that would resist mold/moisture from developing?

Asked By rich78 | Mar 23 17
14 Answers

How to make our walls and HVAC system more efficient?


Asked By Matthew Hicks | Mar 19 17
20 Answers

Do I need to put rigid foam on a crawlspace dirt floor?

I live an old 1890s brace/balloon frame in Virginia (Climate Zone 4). Do I need to put rigid foam on the dirt floor? My contractor is adamant that I need to either insulate the dirt floor or the ceiling above to be compliant with IECC. I was under the impression that I could put a vapor barrier on the floor and insulate the walls with rigid foam. Is there a best practice? And if both are acceptable, how much of a difference does the rigid foam make to the comfort/cost savings? Thanks for any input!


Asked By Chris Thomas | Mar 21 17
10 Answers

Whole House Fan with Blown in Cellulose Insulation

I have been working on installing attic baffles in my attic in preparation to blow in cellulose insulation to a height of 18" to achieve ~R60 for the majority of the attic. Per my calculations and manufacturer specs, my attic has 14 square feet of net free exhaust area 50 feet of ridge vent and 18 soffit vents.

Asked By Josh Z | Mar 18 17
1 Answer

T&G cathedral ceiling air barrier question

We are located in the Finger lakes region of NY and are considering T&G cathedral ceiling. Roof assembly would be Zip Roof Sheathing, un-vented roof with 7" of closed cell foam (R-49). I found a company that uses Lapolla Foam Lok 2000 4G foam with climate-friendly blowing agents. Based on this assembly, I am assuming that I would not need a dry wall layer under the T&G; am I correct?

Asked By Nina Saeli | Mar 20 17
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