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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.

2 Answers

Moisture in sleeper bays over T&G roof decking?

8 years ago. The existing clerestory low slope roof had 2x sleepers over T&G decking with insulation between with sheathing and a membrane roof over. the new addition duplicated this and the entire roof was re-roofed with a new membrane. the 2X T&G decking is exposed to the living space below and is dry...no leaks. the owner is complaining of a "Soft" roof and suspects that interior moisture is trapped in the 2X sleeper bays and rotting. any thoughts? EPD

Asked By ed spencer | Nov 24 14
11 Answers

Plumbing vents exiting ridge cap

Can't seem to find anything in the code, easily missed though. I have a customer who wants a metal roof installed however they have had bad experiences with pipe flashings through the roof and don't like the look of them. While I don't care for the pipe boots, (for metal roofing), appearance they seem to work well.

Anyway, to the question... Is there anything code or common sense wise that says vents couldn't go through the ridge cap? I know it wouldn't look as good but, would limit water flowing over them.

Asked By RMills Miller | Nov 21 14
3 Answers

Retrofit an existing exterior wall to 1-hour rating

I have a small garage conversion project that is within the side and rear yard setbacks and requires one-hour rated walls, eaves for approval. Any thoughts and solutions that balance compliance and a small budget (i.e. demo and rebuild, exterior versus interior modification). USG wall assemblies suggest 1/2" Ply and then exterior wall board (but the garage is now sided with lap siding).

Thank you

Asked By Robert Saladoff | Nov 19 14
1 Answer

Rim joist thermal barrier

The rim joist in my unfinished basement is insulated with 3 inches of rigid polyiso along with one part spray foam to air seal around the edges. My understanding is that building code exempts up to 3 1/4 inches of spray foam in this area from the thermal barrier requirement, but that this exclusion does not apply to rigid foam boards.

Asked By Michael Lee | Oct 27 14
5 Answers

IRC 316.4 - Code interpretation on the use of rigid foam as air barrier on backside of attic knee wall

My insulation plans for my attic kneewalls were to install two layers of 2" eps with staggered and taped seams, then install damp sprayed cellulose in the 2x4 stud cavity, followed by 1/2" drywall. I believe that a thermal barrier is required since I have usable attic space, but I am unclear whether this thermal barrier must be installed on both sides of the stud wall, or only the portion of the stud wall that faces the interior of the attic room. The gray area is whether or not the areas behind the stud wall are considered the "interior of the building".

Asked By Rick Van Handel | Oct 17 14
4 Answers

Basement ceiling insulation required by code — but what about the basement door and stairwell?

Seems like a huge thermal hole in the basement ceiling. Code requires R30 in zones 4 plus for unconditioned basements. What about the bottom of the stairs (to 2nd floor) and exposed stairwell walls? People typically just use an interior door to the basement, right?

Asked By Dwight Harris | Oct 15 14
1 Answer

Is it OK to use Tapcon anchors to fasten the wood plate to the concrete block?

I`m removing a non-functional 6FT. aluminum sliding door and replacing it with a 3ft. steel entry door. When we removed the old 6ft. door we found that the cement blocks (existing) were all loose,cracked & or broke. and the wood was also rotting. My plan is to make a 2"x 8' step wall out of treated lumber and fasten it to the existing solid blocks with the Tapcons. I`m not sure if it is ok to do this that way. Or if I have to put bolts or rods in with cement the core of the block.

Asked By Herb Mathis | Oct 7 14
3 Answers

Expanded polystyrene and water-resistive barriers

I cannot tell whether the ICC-ES has approved expanded polystyrene for use as a water resistive barrier when installed over wood. I can only find that EPS has been approved for stucco. Secondly, I am having difficulty locating the testing procedures described by Mr. Holladay that must be followed when installing insulated vinyl siding, AC71. I note in his article he states flanged windows and Z-flashing must be used. And certain sealing requirements must be met. Any other installation criteria? And if so, are they printed anywhere?

Thank you.

Asked By Daniel Nealon | Oct 2 14
2 Answers

How do you calculate the net free area of an attic vent?

How does a manufacturer of vents determine the Net Free Vent Area of a vent that they put on the market?

Asked By George Sherry | Sep 27 14
5 Answers

Dryer ducting — materials requirements

Hi all,

I've been finding so much mixed information regarding this all over the net. Some places specify only rigid galvanized steel is approved for in wall and attic, other places I find aluminum or galvanized is approved.

Asked By Joe G | Sep 22 14
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