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

Please encourage your building inspector to come here and participate in this Code Q&A; in the meantime, jump in with your experiences -- both positive and negative.

8 Answers

Porch posts

We are building a wrap around porch that extends 6'. Since we know, because of code we have to use 6x6 for the posts for the deck, I have question about the posts that supper the roof.

One way is to use the same 6x6 and extend it from footer to header. We think that since these posts will be 6' apart going around the porch it might seem a bit too bulky.

Does code allow you to replace 6x6 posts with a PVC reinforced porch posts (they are turned and look like traditional porch posts)? Or do we have to stick with 6x6 lumber?

Asked By Matt Cibula | Mar 25 15
4 Answers

What R-value is required on the stem wall of a crawl space?

I am located in Zone 3b, Orange County CA.

Asked By keith messick | Mar 21 15
4 Answers

PEX in Chicago: a gamble worth taking?

I've recently begun the renovation of a frame construction two-flat in Chicago. Its two separate apartments with a basement and an unfinished attic. I have researched PEX and would love to use it to replace all the rusting galvanized metal water supply lines. The main advantage for me is that a PEX manifold and homerun-style system would give both apartments equal water pressure during use ( ie. I don't get a cold shower while my downstairs renter does the dishes) BUT Chicago apparently doesn't allow PEX as a potable water supply line.

Asked By Matthew Lamothe | Mar 20 15
14 Answers

Dense pack cellulose OVER closed cell foam in cathedral ceiling?

I am considering the following roof assembly in climate zone 4a: Will i run into code or condensation issues?

Single plane roof 3/ 12 pitch

1) 6x10 timber rafters 4' OC
2) 2x6 T&G decking perpendicular to and OVER (not pieced in between as a cosmetic ceiling) 6x10 rafters
3) 2x4 sleepers, 4' OC, parallel to 6x10 rafters on top of T& G decking.
4) 2x10 boards perpendicular to and resting on top of 2x4 sleepers, 2' OC.

Asked By Daniel Miller | Mar 15 15
3 Answers

Combine 2 bath exhaust fan runs to vent outside?

I have 2 bathrooms, each with a fan. Both come into the attic as flexible metal about 3 feet from each other. They then snake around and go down to a soffit.

I realize from reaching on this site that this isn't ideal. I'm considering switching them to rigid metal or pvc once they reach the attic, have each continue up slightly about a foot above the attic floor, then slope down toward a new vent in a gable wall.

Asked By Jeremy M | Mar 15 15
3 Answers

Stairway construction and geometry with open back stairs

I'm proposing a 6' wide L shaped open stairs. The treads will be 3.5" thick doug fir glulams. The stringers will also be glulams. I was planning on attaching the treads with angle iron brackets. The treads will be approx 68" wide and will be self supporting from the outside stringers.

Asked By Rick Van Handel | Mar 9 15
8 Answers

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
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