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2 Answers

Foam Insulation on attic floor?

I'm about to insulate my attic. I've read a lot about insulating the attic rafters with foam to create an unvented attic. I've read about laying down a think layer of loose fill on the attic floor in a vented attic. I'm having difficulty deciding between them. And now am wondering about a third option.

Asked By Jason Crawford | May 3 15
14 Answers

Need condensation control — Want a bath vent without another 4" hole outside

Any brainstorming helps.
Have "sealed" window in bath anyway but do not want to open in winter north Iowa.
Radon vent (other side house) condensates.
So I don't want to make another 4" hole for bath vent.
When I turn on radon fan I hear water slosh down in pipe that's horizontal.
And dryer is another 3" hole. That condensates too. (I tried manual fix. See pics.)
And vent stack is another 4" hole.
And gas water heater is another 3" hole out chimney.
And water pipe is another.

Asked By Charlie Darwin | Apr 30 15
3 Answers

Sealing around fire sprinklers in cathedral ceiling

I have a vaulted, insulated, cathedral ceiling in warm California (zone 3) and code required firesprinklers for my tiny guest house (5 total). My piping and sprinkler heads are installed in the center of my 2x12 bays, which will be filled with R-38 fiberglass batts. I have another R-18 of rigid insulation above the roof sheathing. Once insulation is in place, I will install drywall. The firesprinklers have covers for them (similar to photo) with fusible links that will open in extreme temperatures.

Asked By Dan Burgoyne | Apr 29 15
2 Answers

Masonry walls with 2" XPS and rainscreen siding: Anyone have any experience with a fastening system?

There are plenty of resources for fastening foam insulation boards on wood frame construction, i.e fastener depth, spacing, foam thickness, etc. Does anyone have any experience with fastening to masonry construction?

I'm putting 2" of XPS on the exterior of a concrete/CMU building. WRB, 3/4" strapping and fiber cement siding on top of that. I'll fasten the XPS with Hilti IDPs. My question is on fasteners. Any ideas on spacing and embed depth into the masonry? I'm thinking tapcons 12" OC, with 2-3" embed depth, since concrete has less pull out resistance than wood.


Asked By Jonathan Saccoccio | Apr 30 15
3 Answers

2 x 6 wall detail

Hello, We are planning a new home in Glenmoore, Pa. We are located in Southeastern

Asked By william dempsey | Apr 28 15
8 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
5 Answers

Improve efficiency and comfort of this room?

Please see the 2 attached pictures of a room that I would like to improve the efficiency of. The room is between the garage and the main house. I don't like coming in from the January cold only to be greeted by a cold room. I dislike paying the oil man even more that.

Asked By Michael Lee | Apr 22 15
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
1 Answer

Seal (without insulating) rim joist?


I've got a crawlspace in a 1940 home that is reasonably warm and dry, but I want to seal against airflow and spiders. Is it crazy not to insulate as well?

I feel like I can get the sealing done now, and might insulate at a later date.

If I go this route, what is best for sealing the sill plate and rim joist (not sure if I'm using those words right...)? Caulk only, or Great Stuff? If I use Great Stuff I imagine the process being easier -- it's a tight crawlspace -- but I'm not sure if that works as well.

Asked By Firsty Lasty | Apr 25 15
5 Answers

Rim joist at ceiling rafters

Here is a wall section image from several houses I built 10 years ago.
2X6 studson 2' centers. The rafter sits on the joist and rim with 2X6 headers in the wall below.
Considering doubling rim joist over 3' openings instead.
Looking for input.

Asked By Donald Ross | Apr 22 15
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