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3 Answers

I am in the process of shopping for window flashing tape and am running in circles about what brand (and type) of flashing tape to purchase. Obviously, price is a consideration, but I do not want to sacrifice quality and longevity.

Asked By Matthew Michaud | Aug 20 14
16 Answers

I'm building a new house, and would love to hear feedback on the insulation plan. It can be found here: http://lazukars.bitbucket.org/house.png

DESIGN GOALS:

- Have a consistent insulation pattern up from the basement and up through the roof. In this case XPS on the exterior and ccSPF on the interior.
- Eliminate thermal bridges wherever possible.
- Double the insulation required by code

CONCERNS WITH THIS DESIGN:

- Foam Sandwich: The current sandwich of XPS on OSB on ccSPF will create OSB rot. The OSB will not be able to dry to the interior.

Asked By Ryan Lazuka | Aug 18 14
6 Answers

I'm helping a homeowner improve his 1974 ranch, zone 5 Ohio. Attic currently has 6" of cellulose, no air sealing. Blower door results were predictably awful. After removing all recessed light fixtures and fully air sealing the attic floor, I'll be adding more cellulose. There are no mechanicals in the attic, except for a plumbing vent and a little wiring.

Question: are there any potential problems in simply blowing in more cellulose? Even up to touching the roof sheathing near the eaves? (It wouldn't take much, in fact, to completely fill the attic, if one was inclined..)

Asked By Andy Chappell-Dick | Aug 20 14
10 Answers

Hi

I'm new here, and I really appreciate all the great information that has been provided by GBA and its users.

I've been reading a lot about cathedral ceiling insulation, and it seems like it is a fine line between success and disaster when it comes to moisture control. So now I have a few questions myself that I hope someone could help me answer.

Asked By Chris Jensen | Aug 18 14
7 Answers

From all the reading I have done, am I correct that I don't want to use closed-cell and need to use open-cell spray foam in the band areas of floor joists of the basement to 1st and 1st to 2nd floor areas when I have used polyiso sheathing on the outside of the walls?

I believe that is correct because of the perm is so low for the polyiso and you don't want to use another very low-perm product like closed-cell spray foam sandwiching the Zip wall sheathing. I'm just confirming if I read everything correctly.

Asked By john bell | Sep 19 12
1 Answer

I have an attic above my kitchen with 3 interior walls and I am trying to figure out how to insulate it correctly.

Currently the walls facing the bedroom and the entry way have fiberglass insulation.
The floor has cellulose insulation. ~2-3 inches.
The ceiling rafters has ~4" of white fiberglass/denim insulation inside of perforated plastic bags between the ceiling rafters, this appears to be pretty consistent, but I suspect it is leaking a bunch of air.

The roof line is several inches about the existing insulation and connects to the space above living rooms vaulted ceiling.

Asked By John Reuter | Aug 20 14
8 Answers

I am preparing my attic for some additional insulation and was wondering what the consensus is on this subject. I currently have a fair amount of plywood flooring in my attic, installed over R19 fiberglass batts that were laid in between 2X6 ceiling joists. The batts are faced, installed with the paper side down (towards the ceiling sheetrock). I was planning to blow cellulose over these floored areas, leaving the plywood in place, but I thought I better be sure there wouldn't be issues with moisture, etc. Does the plywood need to come up or can I go over it with the celullose?

Asked By Tommy Detamore | Aug 19 14
37 Answers

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
6 Answers

Is the technique easy to learn? How many shims crews would you use on a window?

Asked By David A Flannery | Aug 18 14
13 Answers

New construction, zone 4 on the line of zone 5 (47460).

Bonus room over garage with radiant floor heat in concrete floor.

My floor system has some areas that are blocked off with framing to add support to the ends of the floor in the bonus room. What can I do to insulate those blocked off areas before the ceiling goes in? Would 3.5" of open-cell be enough tot help with keeping the bonus room warm or would it completely block any benefit of migrating warm air from the below garage floor?

Asked By Anthony Hughes | Aug 18 14
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