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1 Answer

Adding a dormer = new ventilation required?

Two friends of mine - one the building owner and the other a contractor - have been renovating an attic and plan to add a 10'x10' dormer. After providing engineering drawings at great expense, our city's building department is now asking for a 'ventilation plan' among other things, in order to get the permit.

It's an old building with no active ventilation in Hamilton, Ontario, Canada. Presumably the Ontario Building Code would mandate the ventilation. I suspect however that my friends are being jerked around by the building department.

Asked By Jonathan Dalton | Dec 12 14
4 Answers

Curious exceptions to the rigid foam thermal barrier

I've noticed that it is common practice for rigid foam to be used on attic hatches and garage doors without being covered by a thermal barrier, which building codes require. Is there some implicit exception for doors/hatches? Or does the small amount of foam used cause it to be simply overlooked?

Asked By Nick Welch | Dec 11 14
8 Answers

Span tables for dead loads above 20 PSF.

Does anyone know where I can find span tables or equations to calculate dead loads in excess of 20 PSF?

Every table I've found including IRC, AF & PA show dead loads of only 10 or 20 PSF. I'm looking to see my options for a pour over a subfloor I'm designing for an addition. I do plan on having a Structural Engineer double check my math and stamp the drawings, I just would prefer not to pay them and extra $500-600 to pretend like it took them all day to do a set of calculations for the floor joist, girder, and columns.

Thanks for any help in advance!

Asked By Michael McArdle | Dec 6 14
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 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
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