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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.

6 Answers

Building a home - to code?

Hello all,

Thanks for taking the time to read my post. I am in the process of designing a small (~ 700 sq. ft.), off-grid house. My intention is to do as much of the design and construction as possible with my own head and hands.

I've been a car mechanic for 10 years, and so have a good understanding of the basic principles of electricity (the house will use 12V wherever possible), HVAC, plumbing, etc. However, I don't have much in the way of hands-on experience with construction.

Two questions (among many) occur:

Asked By Tomas Gray | Apr 23 15
3 Answers

Roof SIPs and 2012 IRC R806

WIth an 8" polyurethane SIP (OSB skins), would the 2012 IRC R806 code apply for roof venting or is that only applicable for ceiling with roof rafters?

Asked By Peter L | Apr 23 15
3 Answers

What suggestions do people have to solve a R-38 roof problem?

We are building a single car garage over a studio apartment in the western North Carolina mountains, Zone 5A. The garage level will be accessed by an 18' bridge. The project is being engineered to address the structural issues of both the bridge and a second level slab to support the car. At this point it appears that we will be building the lower level with Logix ICFs of varying dimensions up to 12" and the second level slab will be supported by 10" Insul-Deck forms. The slab will be 4" thick.

Asked By Jane Greene | Apr 9 15
4 Answers

Is rigid foam as sheathing cheapest way to meet code?

I know: it depends.
I found GBA's detail of 3/4 rigid foam on the framing with 1/2" ply-osb sheathing on top. this gives an easy nailing surface for shingles. So if I can use diagonal bracing, (steel or 1 x4) and xps foam and cellulose this will give me R= 22.25. (Good for Zone 5) and also 18.5+ 3.75. My question is now I don't have to worry about the condensation point because my sheathing is outside my insulation?

Asked By Keith McGuire | Apr 9 15
4 Answers

Insulating outside wall for an in-wall toilet

Hello everyone,

I am considering a wall mounted toilet that has the tank in wall. This would be on an outside wall. I am located in New Jersey 20 minutes west of NYC. How much insulation is required to prevent the tank from freezing ?

The tank would be one stud bay away from an uninsulated steam pipe if that makes any difference, I suspect it won't.

Thanks in advance,

Kurt

Asked By Kurt Kiley | Apr 6 15
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
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