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0 Answers

Can I use rigid foam inside and outside a concrete block wall.

I have a concrete block barn I am converting to a living space. I plan to use Insofast 2" EPS panels on the interior which with the block gives me R-12 (Block at 3 and foam at 9). I would like to get a better R value, by adding foam to the outside. Would this create a moisture trapping problem?

How would I fasten the furring strips through the foam and into the block. I was thinking Tapcon screws.

Asked By Philip Faucher | Jun 29 15
3 Answers

Air sealing exterior walls in a benign climate

Hello Martin,
I am removing and replacing the siding on an old Victorian located in Berkeley, CA which I believe is climate zone 3. After stripping off the old layers of siding, we will insulate, install plywood sheathing, (nailed at 4 at eh edges and 6 in the field for seismic stiffness), and then a drainable house wrap and fiber cement siding.

Asked By Craig McCaleb | Jun 20 15
2 Answers

How to install windows if I build with 2" rigid foam?

Hi. I live in zone 5. I want to build my house not only with 2 x 6 stud walls for extra insulation but also with 2" of rigid foam as that is what the article I read said I would need so I don't have a cold wall.

Asked By Ralph S | Jun 24 15
5 Answers

Insulating second floor band joists from above

A another question led to discussion of band joist insulation, but I have more specific questions that I think warrant a new topic.

I'd like to insulate the second floor band joist in our 1980's colonial house. We're replace the upstairs floors and I think it makes the most sense to insulate from the inside, upstairs floor (as opposed to from the outside or first floor ceiling).

That leaves two options: dense pack cellulose using the 'grain bag' method from holes cut in the floor, or a foam approach enabled by cutting away the subfloor near the perimeter.

Asked By Jeffrey S | Jun 20 15
7 Answers

Tape exterior XPS insulation and housewrap?


Long time follower first time poster.. I have learned so much from this site and appreciate all the knowledge you people share.

We are building a tight house in zone 6 Ontario. The wall stack from inside is as follows:

2x3 uninsulated service wall
2x8 stud wall filled with dense pack cellulose
Cross bracing for lateral strength
2" XPS on exterior
Tyvek WRB
Furring Strips (airgap)
Hardiboard Siding

Asked By kyle lamont | Jun 19 15
2 Answers

Trade offs of closed-cell foam between roof rafters

Hi All,

Asked By William Duerr | Jun 20 15
7 Answers

Filling cinder block with pea gravel?

I am wanting to build a house on some land I bought in Florida. I plan on using cinder block for my outside walls covered with stucco. I want a very high r value. Can I fill the cinder bock with pea size gravel to give the wall a higher r value? What would be the positive and negative implications in doing this?

Thanks, Gregg Webster

Asked By Gregg Webster | Jun 15 15
1 Answer

Need help finding blog post about various construction methods

A year or more ago I read a blog post or article somewhere discussing the various types of construction methods and why high performance construction methods were better than the other methods.

It compared methods like cob houses, earthship, straw bale and basically led the reader to passive/netzero/pretty good methods as being the best from a user and owner standpoint based on construction costs, conventionality, resale value and other factors.

Can you link me to this article/website/blogpost?

Asked By Joseph Malovich | Jun 19 15
7 Answers

I lapped cedar siding over Roxul ComfortBoard

In our area, I have seen a siding detail where they use horizontal 1x4 cedar boards with something like a quarter inch gap between the boards. They don't look like ship lap. I am assuming that they have been fastened directly to the rain screen.

However, I wanted to install 1.5 inch Roxul ComfortBoard on top of the WRB and then the rainscreen. I guess my concern is that this siding style is not a water shedding design.

Does anyone have any experience with this siding style over exterior insulation.
Or have any suggestions on how it could be done?

Asked By Aaron Gatzke | Jun 18 15
3 Answers

SIP OSB panels in contact with raised slab concrete

Our builder decided NOT to use a nailer, and instead placed the SIP panel directly on the 2x4 treated bottom sill plate then nailed the OSB directly into the treated plate. However, the OSB panels, both inside and out sit on the concrete. They did use a closed foam sill seal (blue stuff) so in some cases the OSB is sitting (crushed) on the seal and and many places it is directly on the concrete. Is this a problem? It would seem to us that OSB sitting on concrete or on the thin sealer on concrete would be a problem for the non-treated OSB.

Asked By Scott Moore | Jun 14 15
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