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2 Answers

Venting an existing flat roof

We have a row house in Chicago. The drawing indicate (it seems it was built as drawn) that we have a 1/4" per foot modified bitumen roof. We don't have soffits or ridges (just parapets on three sides and a gutter along the back). The roof structure is min 16" wood roof trusses at the low gutter end and they get bigger at the front. We have R49 Green Fiber blown in cellulose insulation in the trusses. There is no vapor barrier (as the insulation suggested) and there is two layers of 5/8" drywall at the ceiling. We have mushroom vents at 1 sq. ft. of net free area for every 300 sq. ft.

Asked By Trisha Megan | Oct 8 15
11 Answers

Exterior siding layers?

Hello all, I have a quick siding question.

When we spray foamed my shop with close cell spray foam we sprayed against the tyvek(housewrap). It was only one layer. It seemed like the best option we had at the time as I knew I would down the road drop the T-111 osb finished siding and replace it with plywood siding and housewrap and then a cement overlay (making faux stone work out of the cement)

Asked By Max Anthony | Sep 27 15
5 Answers

Discussion of unvented foam-free roof assembly

I've had this article stuck in my to-read list for a while, and just got around to it. I searched to see if it had already been discussed on GBA and didn't see anything, please point me in the right direction if it's already been covered:

This assembly was put together by David Posluszny, whose house in MA has been discussed in depth. This assembly is a bit different, as it's installed in an existing attic and doesn't include any changes to any roof layer from the sheathing out.

Asked By Sam S | Sep 5 15
3 Answers

In a building more than 3 floors, is it better to use header design for top sills or just use(4) 2x4 stacked w/ concrete floors?

We have had some major settling in our builds where the framer and engineer have used (4) 2x4's stack flat as there top sills between each floor of the building which is 6 stories tall on one side and 5 stories on the other, we have had more then 1 1/2 inches in settling in just 9 months and it is causing the plumbing tees to brake in the laundry rooms.

Asked By Andrew Taranto | Sep 9 15
4 Answers

Zehnder ComfoTube code issue

I am an architect working with a contractor/homeowner who is currently building a new home for his family in St. Paul, Minnesota.

He has installed a Zehnder HRV with associated Comfotube piping and insulated air intake and exhaust according to Zehnder's layout and specification. However, our HVAC inspector will not approve the system as it does not meet their ducting requirements - it is not UL listed nor is it a type 0 or type 1 assembly.

Asked By L Alm | Aug 5 15
5 Answers

Building codes

I often see posters refer to building in areas with no codes. Here in Canada, although we have areas in which there are no permits or inspections, the building codes are enacted to cover the whole of each province or territory. People building in areas where the codes are not enforced have the same obligations to follow them as elsewhere.
Are there areas in the US where there are no codes and you are free to build as you like?

Asked By Malcolm Taylor | Sep 2 15
4 Answers

Need an insulation expert!

I'm building a new home and it's at the insulation stage. It's 2 story with a steep pitch roof.(8/12 for the main part of house, 12/12 over the garage bonus room and 2nd bonus room over the master bedroom) The attic is vented and has soffits. I'm in zone 2, hot and humid south Georgia.

I had a spray foam guy offer quote 5 inches open cell (r19) on roof line and open or closed cell @ r13.

I'm concerned about not being at code but some literature suggests r20 spray on roof is ok.

Asked By Brock Herrin | Aug 22 15
2 Answers

No soffits & under-insulated roof create mold concerns

Hello All,

I have a 116 year old home in Denver, CO (zone 5B) where I had no insulation in my 1.5 story home. I hired an insulation contractor to insulate my home that had no insulation and freezing pipes, which they did. Now I'm concerned about mold from condensed water vapor. I'd like to make sure it's all to code and safe from concerns now that we are going to re-roof from hail damage.

Asked By Peter Czarnecki | Aug 19 15
5 Answers

Lunos E2 HRV

Does anyone have experience in Canada getting permission from local building inspectors to install the Lunos e2 HRV's? We have been shut down now for months trying to get sign off on them for 540 sq ft micro-lofts we are building in Halifax ( Locating tangible evidence the units have been installed elsewhere in Canada will establish credibility. We have performed a blower door test and engaged local mechanical engineers to vouch for the equipment based on the data established in the test, however, we are still facing opposition from compliance.

Asked By Kerry Lynch | Aug 11 15
10 Answers

Anybody familiar with British Columbia building codes?

I am building a home in BC, and plan to use Lunos e2 for my HRV. There is a lot of stuff about ventilation and HRV in the latest code revision (Dec 2014, I believe). Is there, by any chance, anybody out there familiar with the BC codes that can tell me if I am going to experience issues trying to use the Lunos fans?

A couple things that I am concerned about (off the top of my head).

Asked By Stephen Youngquist | Jul 29 15
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