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21 Answers

Ice & Water Shield membrane installed under roofing is buckling

After over a month of photos documenting the problem of vertically oriented ridges, my contractor has finally offered to fix the local bulges.

The roof structure below the roofing is a conditioned attic with an R-60 Deep Energy Retrofit roof (cellulose in 2x12 cavity, plus 4 in. polyiso wrap over 1st layer of sheathing, plus 2nd layer of sheathing over polyiso).

Asked By Erica Downs | Aug 14 15
3 Answers

Split air line set deformation question

Hello All,

I'm installing my my own split-air system with three zones. One is an 18k ceiling cassette that has a 1/2" and 3/8" line-set. Despite my best efforts, the 1/2" copper got deformed when making a corner. It's not kinked, exactly, but definitely deformed. So my question is, will it work with the deformation or have I botched the line-set, altogether? I've attached pictures.

Asked By Scott Mcllarky | Aug 20 15
7 Answers

Detailing stoop slab: concrete to wood

I am building a new house which will be clad in full-thickness natural stone veneer. A stoop slab just outside the front door will be poured on top of a cold room that's part of the foundation.

My concrete contractor, of course, wants to pour the slab right against the rim joist. That's not going to happen. But what SHOULD happen?

With the masonry veneer, the wall above includes a 1" air space--should I have the guy leave the 1" also between the slab and the rim? How would I ensure proper water drainage out of that space?

Asked By Andy Chappell-Dick | May 18 13
9 Answers

How to I properly insulate and seal an HVAC plenum through a garage slab?

Hello,

I have a difficult situation. I had to completely gut the existing HVAC system in my 1991 house due to numerous major issues (flex tubing like Swiss cheese facing into the plenum, kinks, leaks, a branch off the end of the trunk, returns in the wrong place, missing registers in some rooms, too many in others, etc. After ripping everything out in the house and basement, Now the trunk is all metal, sealed, insulated, properly sized, reduced correctly, dampers on all branches, etc However, I found another problem.

Asked By Jeff Richardson | Aug 10 15
3 Answers

Furring orientation over exterior mineral wool panels

Our office (architectural) is considering using exterior mineral wool with furring strips to create a rain screen. The assembly would be like this, from interior to exterior:

5/8" GWB painted w/ semi-permeable paint
2x6 studs w/ r-21 fiberglass batt insulation
1/2" plywood sheathing
Henry Blueskin WRB (fully adhered housewrap w/ 29 perms) which would double as air-barrier
2" Roxul Comfortboard IS
1x furring strips
vertical wood board siding

Asked By Daniel Stewart | Aug 17 15
13 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

Asked By kyle lamont | Jun 19 15
9 Answers

SIP vs ICF

I know this is a topic that has been talked about a lot, but I do have a question we are mulling over in designing our house.

I have been pricing materials and it seems that both ICF and SIPS are going to cost relatively the same. (We are doing labor ourselves.) With the ICF we were going to get continuous R value of 24 and no air leaking or thermal bridges. We were going to bring this up to the roof where we would use SIPs that are 6 1/2" for an R40. We were then going to either dense pack below the sips or add another couple inches on top to try and bring it to around R60.

Asked By Jordan Schiele | Aug 18 15
6 Answers

Insulating a wall with loose and blown-in foam

We are in Zone 6 . Most builders here recommend the code which is 2x6 walls with R20 loose insulation plus optionally 1" of rigid foam outside of the plywood . One builder recommended R-20 loose insulation and 1" of blown in foam between the loose insulation and the vapor barrier. He said it creates a better seal.

I haven't seen this method, is it a sensible alternative to what the other builders are recommending?

Asked By John Ball | Aug 19 15
3 Answers

Proper nailing pattern for reverse board and batten

I am in climate zone 4C and am planning on installing douglas fir, rough cut, kiln dried, and stained reverse board and batten on the home I am trying to build. I was hoping to receive some advice on the proper nailing pattern for reverse board and batten. Most things i find deal with green standard board and batten. I was planning on using screws. Would deck coated screws eventually bleed through and stain the wood? Do I need to use galvanized or stainless? I was thinking of using the deck coated torques finish head screws, is this a bad idea? Thanks for the advice.

Asked By Kail Zuschlag | Aug 17 15
5 Answers

Proposed approach for fixing brick/poly wall issues

My house was built in Kentucky in 1996. Exterior walls were built with the following order/characteristics:

-- Full brick siding - rope-style weeps but no vents
-- 1/2-inch air gap between brick back and Tyvek - there's lots of trash mortar, much of it smushed flat against Tyvek; gap is open at top, good air flow in soffit
-- Tyvek - probably lapped not taped ()
-- OSB sheathing
-- 2x6 studs with R-19 Fiberglas bats
-- poly
-- drywall with latex paint

Asked By Mark Jeantheau | Aug 17 15
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