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1 Answer

Foam insulation — venting before covering?

in a previses question i asked about timing of batts installions
in flash and batt
respondes were very helpful
but still have concerns manf. web sites say wait 24 hours
depending on condition and amounts of foam
i hade read an artical in JLC a while back about problems with foam
were it was stated if you can smell it its still off gasing
most jobs where were going to install batts after foam contracter has finished
seem to have oders well past 2 or 3 days
as so ive read in manf. spec. that if existing attic is being sprayed

Asked By Kevin Mccarthy | Oct 29 15
12 Answers

Insulation Baffle in *corner* of hip roof

I am installing my insulation baffles for the attic. I have run into a problem. My roof is a hip style and the corners have a main bridge truss that the smaller guys attach to to form the corner. The first two immediate rafter bays in the corner have very little room. The next two on each side have a little more room as you can see, which I just cut the insulation baffle at an angle to fit in.

Asked By Nicholas C | Oct 27 15
1 Answer

Pole barn — ceiling vapor barrier?

I live in Alaska.. far northern Zone 7 probably zone 8. I have a pole barn that has metal siding and a metal roof on large wooden rafters. Shop/Barn is 45x50x14 and 8/12 pitch with stud walls and lathe is currently in place for the ceiling. The attic area as you can see is quite large due to the size and pitch of the roof
I am thinking about using metal interior panels as the ceiling (basically metal roofing without the UV paint protection) as opposed to sheet rock.


Asked By James Williamson | Oct 27 15
3 Answers

GBA page not working

All i get is a blank page, i'm on windows 8.1m firefox 41.0.2

Asked By Alan B | Oct 27 15
12 Answers

Design Charrette: General Building Envelope Questions for Mixed-Humid Climate

I'm in need of some focused input on the overall insulation strategy for a home I'm designing, and rather than taking hours upon hours searching through the archives and reading what now seems to be seemingly countless (and often divergent) opinions on these matters, I'm hoping through a quick online charrette a general consensus could be found to help me and my client understand the best route to achieving a fairly high-performance home for a mixed-humid climate (only!) in the Blue Ridge Mountains (meaning we don't get quite as high humidity levels as lower elevations, but can get some fairl

Asked By Marc Manley | Oct 26 15
2 Answers

How much time after spray foam should batts be installed in a flash-and batt job?

Due to off-gasing of closed-cell foam, how long should you wait before batting?

How would one check if curing is complete?

If batts are installed to soon, will they then retain the gases?

Asked By kevin Mccarthy | Oct 27 15
2 Answers

Dryvit application

Hello All,

Towards the tail end of our house build and still not sure what we want to do with the canopy. Original plan was to Limestone it but the budget doesn't allow it any more.

I am now thinking of Dryvit it with Limestone finish where they cut the V-groove and all that into it. I am being told there's a special product which is twice as expensive as the regular one which will give it the limestone smooth finish.

Asked By yasir khan | Oct 26 15
8 Answers

Fibre-board sheathing

When posters recommend fibre-board sheathing as an alternative that is more forgiving of moisture, what exactly are we talking about? Are there a range of different products with different permeability and characteristics?

Asked By Malcolm Taylor | Oct 26 15
3 Answers

Adding polyisocyanurate insulation with a laminated air barrier

Good afternoon,

I’m currently executing a complete home renovation of a bungalow located in Montreal, Quebec and would like to increase the insulation of the above grade walls.

The existing envelope of the house is composed of:
- 3.75’’ brick;
- 1.5’’ air;
- Asphalt paper air barrier;
- 0.5’’ Tentess;
- 2’’ solid wood structure;
- 0.5’’ tentess;
- kraft paper;
- 0.5’’ wood furring;
- 0.25 gypse, and;
- 0.5’’ plaster.

The proposed new envelope will be composed of :
- 3.75’’ brick;
- 1’’ air;

Asked By Alessio D | Oct 19 15
8 Answers

Air barrier around shower mixing valve

Any ideas on recommended detailing around a shower mixing valve?

My primary air barrier is sheet material on dry side of wall (membrain). 2X6 roxul insulation with sheathing and then another 1.5" of roxul comfort board on the exterior.

I've spent quite a bit of time caulking seams at tops and bottoms of stud bays, sealing up all possible holes in my sheet air barrier but now I'm scratching my head on the shower mixing valve detail. Insulation and vapor barrier is in...



Asked By colin slade | Jul 14 15
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