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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.

9 Answers

Can I reuse single-pane steel sash windows?

A client would like to restore some window openings that were bricked-over by a previous owner. The original single-pane steel sash casement windows had been stored, and are in excellent condition. The building department views these "restored" openings as "new" openings, and requires compliance with the energy code, i.e. window U-factor of 0.30 or better. (The default value for these windows is U=1.20 per Table R303.1.3.)

Asked By Robert Drucker | May 21 15
6 Answers

Vinyl siding renovation


Asked By Chris Felker | May 14 15
3 Answers

R-38 ceiling and spray foam

If one sprayed 5" of open cell spray foam on a ceiling area, that would equal to around R-17.5, correct?

Now code requires R-38 minimum for the ceiling in this area. There is no "performance value" of R-38 in 5 inches of open cell spray foam, right?

That would be a marketing line bunch of nonsense as 5" of open cell is R-18 avg. and anyone claiming it is performing like R-38 is lying. How would the code department buy into this nonsense?

Asked By Peter L | May 15 15
2 Answers

Basement perimeter wall construction

My basement has a full perimeter sump pump; drainage mat on wall from 1 foot below ground level to loop into the plastic cove that empties to the sump drain below; limestone foundation walls; penetrating sealer on the concrete floor.

I plan on installing light steel perimeter walls where no steel will touch the limestone foundation walls. Closed cell spray foam, treated with a fire barrier, will be installed professionally after plumbing and electrical runs are completed.

Asked By Donna Agah | May 15 15
3 Answers

16 ga. or 18 ga. wire for lighting circuit?

LED lights are 5 watts.
Do we still need 12 ga or 14 ga wire?

Asked By C Darwin | May 7 15
7 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
6 Answers

Garage footing - 42" wall without forms?

I dug down 3' holes for 7' (8'?) long and 7" wide round fence posts with hole digger about 10 years ago. Some wave in 20' dog eared fence.

Now would like garage to go there since snow piles in there where car sits.
Have to dig out 8' posts and make nice trench for garage foundation.
(I'd like to stir my own concrete too.)
New garage will join existing garage back. So back to back facing and joining garages.
So 2 side walls I think I can manage myself.

Inspector neighbor just says go 42" down--even mortared rocks are ok.

Asked By C Darwin | Apr 29 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
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