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0 Answers

closed or open cell

you have helped me before. i have decided to do a spray foam insulation. the building is pole barn type build [wood] covered in sheet metal. it has a concrete floor,insul garage door an it will have a/c only, it also is located in central fla. i,ve had 3 different contractors with 3 diff ways of doing it. one is closed cell on walls an roof an he said 1/12 "" is all thats needed. he had the best price [ still not cheap]. the next guy wanted to close cell the roof an open cell the walls.

Asked By bill metzger | Jan 31 16
4 Answers

Can you install batt insulation in the cavity of a double stud wall?

Hi, I'm building a cabin in upstate NY and trying to achieve an R-50+ wall. I want build a double stud wall assembly with Roxul Comfortbatt. I'd like to install a continuous layer of batt at the wall cavity (in addition to between the studs themselves). The manufacturer advised against this. They said the batts won't stay in place unless secured between two studs. I've been seeing examples online however, that suggest you can do this. They show double stud wall, cavity filled with dense packed cellulose or batt - unless I'm misunderstanding. Can anyone advise on this? Thanks in advance.

Asked By Nora Meehan | Jan 30 16
22 Answers

Off-grid PV solar for domestic HW

I am planning a small off-grid home and would like to send all surplus energy from the 4.8 kw solar array to a standard electric water heater, probably of 60 or 80 gallon capacity. In effect, it would serve as an additional "battery" once the main battery bank is fully charged. Does anyone have any suggestions or experience on how this might be done in a fairly simple and reliable fashion?

Asked By Peeter Vihvelin | Feb 22 13
7 Answers

Insulation plan for bonus room above garage

I am in MN(zone 6), working on my new construction.
It has an attached garage with a bonus room above it. I don't plan on finishing it right away but would like to plan how I am going to insulate it.
I have sheathed the roof deck with 7/16" zip sheathing. It will be covered with Cedar shakes. I have already roofed almost half of the house and am slowly making my way towards the garage.
I am considering both vented and unvented assemblies.

One of the possibilities is:

Cedar shakes with 30 lb felt paper interlayed
1 1/2" above deck ventilation
Zip sheathing

Asked By asim majeed | Jan 26 16
3 Answers

Wall systems decision

I am designing and home in the outskirts of Santa Fe, NM (climate zone 5B / elevation 6800 ft.).
I am interested in energy efficiency, low maintenance and overall best choice for this climate.
(note: we are planning to use geo-exchange heating and cooling + PV's to minimize energy costs as the site will only have electrical and propane fuel sources)
We all know pretty well the pros and cons of double wall frame construction for this area.

Asked By Abelardo Ruiz | Jan 25 16
15 Answers

Finishing the attic space - Best insulation plan?


I'm planning to convert my unfinished attic space into an entertainment room. It has a cathedral ceiling, knee walls and flat ceiling. I'm looking at fiberglass:

The current plan is:

Cathedral (2x10) - Vent baffles with R38 faced fiberglass batts
Flat Ceiling (2x8) - R-49 faced fiberglass batts
Exterior Walls (2x4) - R15 faced fiberglass batts
Kneewalls (2x4) - Roxul Safe n Sound (to keep noises from entering bedrooms below)

The attached plan shows it better.

Asked By Jason McCoy | Jan 25 16
25 Answers

Our builder insulated our cathedral ceilings with dense pack insulation. Now we are having condensation and mildew problems.

We have contacted a local roofing company and it proposes to remove our shingles and sheeting and then remove all the insulation. They also propose removing siding where necessary. Cost: $140,000. Is there another solution?

Asked By James More | Jan 22 16
5 Answers

Rigid foam sheathing moisture accumulation

I would like to add 2" of exterior rigid foam to a 2x6 wall in climate zone 6. This is a new build. After reading your article "Calculating Minimum Thickness of Rigid Foam Sheathing" it sounds like with only 2 inches I am risking moisture accumulation behind the rigid foam. I've seen that Dupont offers a "Tyvek Drain Wrap" material specifically designed to go behind exterior rigid foam that allegedly allows any condensation behind the foam to drain. Does anybody have any experience with this particular material?

Asked By David | Jan 20 16
3 Answers

Basement insulation in Minnesota


Asked By Jason | Jan 20 16
4 Answers

How to insulate a metal roof that does not have any roof decking?

We are building a red iron framed barn house. The house has all roof framing made out of red iron. A metal roof is being installed on the red iron frame work of the roof. The roof does not have any wood in it. All metal trusses. We are installing a metal standing seam roof on the roof and it will not have any roof decking. My question is: how to spray foam insulation on roof with out spraying directly to metal roof pannels? So when I have to remove the pannels in the future due to an unforseen reason I will not have to redo my insulation.

Asked By Holley | Jan 19 16
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