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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 (urbanrenewable.com). 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
2 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
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
2 Answers

Steel Quonset hut — 1 hour fire rating?

Hello,

Asked By J Choi | Jul 31 15
5 Answers

Insulation for condensation control changes from IRC 2009 to 2012

I'm building a small house in Portland Oregon, climate zone 4C marine (according to 2009 IRC). I have 2x12 rafters with blown cellulose, then a layer of taped plywood sheathing for air barrier, then 3" of XPS followed by another layer of ply and the roofing on top of that. Since the ceilings are vaulted, it's an unvented attic situation, so I'm worried about moisture. I've got R36 in the cellulose and R15 in the XPS.

Asked By Tom Frisch | Jul 26 15
20 Answers

Buyer education versus a good code and intensive enforcement of it

This is kind of a general question. I'm seeing more and more issues coming up on GBA questions and answers regarding shoddy construction that homeowners are having to deal with. I read it recently in Peter L's description of some builders in the Phoenix area. This is most concerning when one is having a new home built, or purchasing a previously built new home, and it has subpar construction.

Asked By Eric Habegger | Jul 21 15
3 Answers

Do I need to cover XPS in an attic?

I know codes vary from town to town but I'm looking for the general code requirement/interpretation for this. I have used R-10 2" XPS for the interior of basement walls. I know that it must be covered with drywall or another similarly accepted material for compliance and I have done so. I also have learned that the exception is between floor joists at the rim joist and have benefitted from this exception...wouldn't that be a pain of a detail! I now have to build an enclosure that had never been built for a fire box that protrudes into the attic over the garage.

Asked By Tyrone Powell | Jun 22 15
4 Answers

Insulating the Interior of Poured Basement Walls

This picture is from building science.com and shows an ICF foundation with insulation under the slab. My question relates to the interior wall plane where the floor slab meets it. Does the code require that the slab make physical contact with the concrete wall? If it does, how do code officials deal with situations like this one with ICF foundations? I wanted to have a similar insulation setup on the interior with poured walls. Prior to pouring the floor I would lay rigid foam along the ground and up the wall - thermally isolating the slab.

Asked By Brian W | Jun 21 15
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