Community: Building Code Questions

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Does green building seem to be at odds with the code?

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1 Answer

What is the correct climate zone.

Can anyone point to a web site that will be zip code specific to determine which climate zone you are located. The Department of Energy web site leaves something to be desired. I cannot determine a clear explanation of climate zone 4 and 4 Marine. It seems there should be a site to enter zip code or address and get definitive information regarding climate zone.

Asked By william dempsey | Mar 1 15
3 Answers

Insulating outside wall against moisture

I have an outside wall with soil piled up due to grading against a wall. I heard installing an "insulation curb" would help. What kind of people should I hire to re-work it and install "installation curb"?

Asked By Anthony Ng | Feb 18 15
3 Answers

Can closed-cell spray foam be applied to the underside of the decking of a flat roof that has rigid insulation & EPDM above it?

I am from Winnipeg, Manitoba (Climate Zone 7a).
I'm planning to build a cottage with a low-slope roof (0.5:12).
I was planning the layers like this (top to bottom):

  • EPDM (fully bonded)
  • 1.5" HD Isoboard
  • 5.5" rigid XPS insulation
  • 3/4" T&G plywood decking
  • 12" I-joists with 3" closed-cell spray foam applied to underside of plywood
  • drywall

I'm assuming that that the close-cell spray foam will be acceptable as a vapour retarder.

Asked By Jake Harms | Feb 19 15
10 Answers

Vapour barrier is installed...should I remove it?

My insulators have finished and installed a 6 mil vapour barrier....they blew in fibreglass insulation in the 2 by 6 cavity .I have 2 layers of EPS totalling 5 inches on the outside walls and have staggered the seams. The building inspector has passed the insulation .My builder is unsure of the need for an interior vapour barrier . The inspector said it's there now so leave it. My advice from this forum is to get rid of it or slash it to make ineffective . The house is being built in zone 6 climate in Canada .

Asked By bob holodinsky | Feb 17 15
4 Answers

Vented/Unvented Cathedral

My original design for my cathedral ceiling involved 2x12 rafters filled with fiberglass batts or cellulose. Then with 1" xps foam installed directly on top of the rafters. I planned on installing purlins on top of the foam board with metal roofing screwed to the panels.

To comply with the code for unvented cathedral in Indiana, I am supposed to have r-15 of foam above the sheathing. I don't intend to have conventional plywood or osb sheathing. It seams like all the code is made to vent the moisture off the sheathing.

Asked By Nick Mason | Feb 5 15
3 Answers

Does code require fireproof caulk around electrical boxes & light switches?

We had a blower door test on our house following a major renovation (ACH50 = 4.56 on a 1920s Bungalow, Zone 2A). Several leaks identified, along with my plan to airseal them:

1) Electrical boxes & light switches (photo attached) - Caulk the gap between the electrical box & drywall, add a foam gasket behind trim plate, caulk plate to wall (on inside) & install child safety plugs in unused outlets

2) Base of interior door jams (photo attached) - Caulk

3) Exterior door weatherstripping (copper) - Bend back the copper for a more rigid fit

Asked By Robert Hallenbeck | Jan 31 15
2 Answers

I will not be able to finish my deck for months but would like to get a final inspection signed off.

Suggestions for temporary deck railing that will meet code would be much appreciated. We are in Washington State.

Asked By Jacque Hyler | Jan 29 15
6 Answers

Can an applied veneered cut stone on the exterior of a house in Houston, TX hang over the property line?

Any help appreciated, be it by links, PDFs, response.
Thank you

Asked By Rodrigo Marron | Jan 20 15
3 Answers

Masonry heaters and U.S. building code?

From what I understand US codes require two walls of masonry. My question is can the outer wall requirement be met with " stuco", and if yes is there a minimum thickness? Apparently European codes allow "single wall masonry heaters.

Asked By Jerry Liebler | Jan 16 15
11 Answers

Roof Trusses 4' oc?

Would roof trusses spaced 4' oc fall outside prescribed methods for stud construction of a house in the 2012 IRC and therefore require approval from an engineer (other than the engineers at the truss manufacturer)?

Asked By Jeff Cooper | Jan 9 15
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