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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

In Green building techniques | Asked By Daniel Stewart | Aug 17 15
13 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

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


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.

In Energy efficiency and durability | 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?

In Energy efficiency and durability | 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.

In Energy efficiency and durability | 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

In Green building techniques | Asked By Mark Jeantheau | Aug 17 15
6 Answers

Air sealing and roof venting in kneewalls


In Green building techniques | Asked By Regina Schweinsberg | Aug 17 15
5 Answers

Windows with different sun exposures on same wall -- Glazing options

We are planning to build our house with a front porch, but the porch will not run from corner to corner. A room at the corner of the house will have two windows on the same wall, about 5 feet from one another. One will be under the porch, so fully protected from the sun, but the other will be out from the porch so it will be fully exposed. The wall these windows are on will be angled about 40 degrees East of true South.

In Green products and materials | Asked By Clay Whitenack | Aug 19 15
5 Answers

Metal angle/drip edge under exterior rigid foam

I'll see if I can word this question correctly.

Wall Assembly is the following:

2x6 stud
3/4 plywood
1.5" XPS foam
3/4 furring strip / ventilated rain screen assembly
Hardi Plank Siding

I see a lot of details in my research for exterior foam and ventilated rain screen assemblies that include a field formed metal angle around the bottom edge to protect the bottom of the foam and direct any water away from the house.

How much space should I leave between the metal angle and the bottom of the assembly to allow for ventilation air?

In Green building techniques | Asked By kevin field | Aug 19 15
2 Answers

BTU need for a 60'(w) x 100'(l) x 12'(h) building.

This is hypothetical building, with R40 roof, and R38 wall on concrete slab foundation/floor, no window. Basically a warehouse in the desert with daytime high of 115F but need the interior to be around 73F.

How many BTU it will need? Would an increase to R60 roof help?

In Energy efficiency and durability | Asked By pete rosegardner | Aug 19 15
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