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6 Answers

Trapped moisture on SIP roof

I knew SIPs were the Achilles heel of my 100% engineered house design, But because of inattention to detail, heavy rains at a critical time of my house build pushed water underneath the PVC membrane (applied on mechanically fastened DensDeck) onto my SIP. It happened the night before the adjacent wall could be spray foamed to properly seal off the membrane. Unfortunately, the spraying was later done to the walls and the underside of the SIPs without knowing there was water present.

In GBA Pro help | Asked By Edward Mallett | Jun 29 15
42 Answers

Spaceloft my only option?

Needing to get all the R value I can get in a limited space. From the cob webs you can see that this is an old house. Recently installed Cedar shakes with felt underneath over the 2x4 studs or mini rafters...
I think they call this a skip sheathing install of the cedar roof?
So, 3.5" is all we have but we'd like to get to an R50 or thereabouts in our upgrade of this 1925 built home in Climate zone 4C.
Spaceloft seems the only option. With an R10 per inch. It comes in 10 cm thickness, 0.4".

In GBA Pro help | Asked By Jan Verschuren | May 29 15
3 Answers

Re-roofing a tar and gravel home

I have a small (approx. 900sq ft.) home with a flat tar and gravel roof. I know the roof is at least 10 yrs. old and I have not experienced any issues within the house from leaks or whatnot. I have however noticed that the overhangs of the roof that stretch the perimeter of the house at 2 feet, have become soft and fairly weak when stepping on them. They also show some signs of mold on the underneath side of the sheathing. I have not noticed these problems with the portion of the roof that covers the house.

In General questions | Asked By Jared George | Jun 30 15
10 Answers

Tape exterior XPS insulation and housewrap?

Hello,

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:

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

In Green building techniques | Asked By kyle lamont | Jun 19 15
7 Answers

Did I goof badly? Metal bracket against exterior sheathing

My typical wall section on part of my house is 5" of stone, two layers of 2 1/4" EPS rigid foam, Grace waterproofing, plywood sheathing with 2x4 studs and blown fiberglass between the studs.

In Energy efficiency and durability | Asked By Gary Dick | Jun 30 15
13 Answers

Is it advisable to use nail base insulation panels over a roof insulated with closed cell spray foam?

We are renovating an old railroad station, turning it into a residence and are gearing up to put new roofing on the building. Built in 1888, the building has massive overhangs on all sides and the rafters are mostly 2x6s with 4x6s spaced about 8' apart supported by large brackets. We had planned to use closed-cell spray foam insulation in order to get the maximum r-value in the relatively shallow rafter bays. Also, we want to maximize the available head room in the second floor rooms. The underside of the roof will also be the ceiling with t&g beadboard installed directly to the rafters.

In Energy efficiency and durability | Asked By Jodi Gunderson | May 29 15
3 Answers

Cut and cobble polyiso then spray foam

Hello everyone,

In Energy efficiency and durability | Asked By jason hood | Jun 28 15
1 Answer

Would insulation blown into an exterior wall eliminate bird infestation?

If there is room for the birds who have made golf ball size holes in our exterior wood siding and are raising a bunch of babies in there, could we eliminate the birds and get extra insulation at the same time. We think the birds are the invasive European Starlings, not nice birds.

Thank you for your help, Cathy

In Energy efficiency and durability | Asked By Catherine Rodner | Jun 29 15
1 Answer

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.

In Green building techniques | Asked By Philip Faucher | Jun 29 15
9 Answers

How to attach 4" EPS foam to exterior of basement wall below grade?

I am gathering materials for an expansion and reno of an existing home in zone 7.
I will be adding 4" EPS foam above grade wood framed portion on the renovation side of the building (850 sq ft) as well as to the new construction (1000 sq ft) using 6 1/2 inch screws (thanks Dana for pointing me in the right direction on that detail).
I am struggling with details on how I will attach the 4" EPS to the below grade concrete AND whether to use a drain wrap product against the concrete wall like Platon Foundation Wrap.

In General questions | Asked By tim brown | Jun 27 15
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