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6 Answers

Taping of Roof Sheathing / Wall to Ceiling Vapor Barriers

We building in climate zone 6A. We have planned unvented cathedral ceilings and we are planning to do 4" (or maybe just 2" depending on cost) of closed cell spray foam applied to the underside of the roof deck. We are then going to net and blow in fiberglass to the remainder of the cavities between the 16" TGI's.

I'm planning on the closed cell foam being my air and vapor barrier on the roof. On the walls the my air barrier will be the taped sheathing and the wall vapor retarder will be latex paint.

Two questions:

Asked By Steve Mackay | Mar 21 18
6 Answers

What is the minimum depth a water line must be in zone 6 and pure medium to course sand?

I know there must be code requirements but there must also be some scientific way to know at what minimum depths a well water line will not freeze, because I'm thinking the soil composition would be a significant factor. I am in zone 6 in Traverse City, Michigan in pure medium to course sand and on a hill 35 feet above a small lake. The sand is very dry.

Also, can I use Pex underground from the well to the house? I have heard that it is somewhat flexible and resistant to cracking or bursting if the water freezes.

Asked By user-6992381 | Mar 20 18
27 Answers

Insulate this!

This one-room addition has no foundation. There is insulated in walls (likely R11) and ceiling (likely R19 - certainly no more), but not in the floor. As you can see, outdoor air can simply pass through the open space under the floor. When the flat EPDM roof needs to be replaced in 5-10 years, we will install exterior foam board outside the roof deck. Heating is primarily warmed air from rest of house or propane fireplace. Cooling is AC from rest of house.

I'm considering digging 2' out under the floor, and sealing the underside with foam. What approach would you take?

Asked By Emerson | Dec 21 17
0 Answers

Air sealing a chase

The bottom cabinet in these built-ins was never finished (Photo 1).

Photo 2 is a vertical look up the chase behind the cabinet. To the rear is a poorly insulated exterior wall. At the top of the chase, to the left is an unvented flat roof above a first floor addition. At the top of the chase, to the right is the second story of the house.

This entire area feels very leaky.

How would you air seal this space?

Asked By Emerson | Mar 21 18
2 Answers

Insulating block walls

I am currently remodeling an old gas station. The exterior walls are cinder block. The building is 26 feet by 48 feet with 12 foot high walls. One third of the building (26 feel by 16 feet) will be used for a meeting area and have two bathrooms. All of these walls have been framed up with dimensional lumber. The perimeter walls of this space have been insulated and a vapor barrier applied followed by drywall. The remainder of the building will be used as a heated storage area with no interior insulation. The exterior of the building is to have LP smart siding.

Asked By man of steele | Mar 20 18
1 Answer

Ideal window depth to minimize window perimeter thermal bridging through frame

I am replacing the windows and redoing building envelope in my 30 year old house. Currently have 2x6 framed wall, covered with 5/8 tentest type fibreboard and then wood siding. Windows are original 30 year old solid wood. I am replacing windows with the following: Basic flush mount vinyl high efficiency windows, 4 5/8 thick with interior jamb slot for interior trim to be added to.

Asked By user-7038920 | Mar 21 18
6 Answers

slumping of siding from nailing through rigid foam

Thanks for any assistance you can provide.

I am wanting to add additional insulation on the outside of our home. We are in zone 6. Our current walls are 2x6, 24 inch on center with 6 inches of fiberglass insulation, 7/16th OSB with tyvek. We have lived with cedar siding for 30 years and are now wanting to remove the siding and windows. Replace the windows and us LP siding.

Asked By user-7005676 | Mar 20 18
1 Answer

Tips for obtaining recycled scrap insulating board?

I was able to obtain a truckoad from a roofing company several years ago, but now I'm having trouble sourcing it.

Any hints from the experts? I'm in North Texas.

Asked By Lynda Robertson | Mar 21 18
9 Answers

ERV with HEPA filtration options

Hi Everyone,

Been a lurker here and I have a question and looking for advice.

Im building a new home, my previous home burned down. Im in Southern California, climate zone 3b, and my house will be pretty air tight, built with sip panels and using mini splits for heating and cooling. House is around 4300 sqft, I talked with some people and they recommended 3 Panasonic FV-04VE1 ERV units for ventilation throughout because of the lack of attic spaces and expenses.

Asked By m4tr1x | Mar 20 18
5 Answers

Brick Ledge help with Rigid Foam Over CMU


I am doing a custom new construction home and am trying to get some economical ideas on how to best provide a brick ledge when I add up to 4" of exterior rigid foam in zone 5.

Currently, the plan is to have a 10 inch CMU basement, that then steps down to 6 inch CMU for 2x6 stud walls, the other 4 inches is to be used for brick that starts just below grade. The brick travels through the first floor. The second floor will be vinyl double lap siding.

Asked By Wayne321 | Mar 20 18
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