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8 Answers

I am overwhelmed with the wall cavity options and need advice

After researching for the last few months on this website, buildingscience.com, and PHIUS.org I am just overwhelmed...buy maybe under informed. I am an owner/builder (former construction project manager...mainly responsible for foundation and electric work then) and this will be my second house. Most of the case studies and articles I have read are about homes in climate zones far more extreme than what we typically have in TN.

Asked By Andrew Bennett | Mar 4 15
1 Answer

Recommended taping of plywood and foam layers

I am building a small casita (500 sq. ft.) in Northern California in a mild climate with hot summers. My wall framing is 2x4 w/ 3/8 continuous plywood shear (also insulated w/ R-13 fiberglass batt insul.), which I will cover with two layers of 1/1/2" Polyiso (Firestone) insulation (has fiberglass reinforced face). I will cover everything with Tyvek housewrap and fasten 1x4 battens creating a rainscreen, and attach lath and plaster as an exterior finish to the battens.

Asked By Dan Burgoyne | Mar 5 15
0 Answers

Critique of cathedral ceiling and wall design - Swedish Style

Planning on building a 1-1/2 story, well insulated home using 14” I-joists as the rafters. Then running 2 x 4” horizontally. The I joist cavity will be air sealed. The 2 x 4” cavity will not. I will have an ERV. This idea is a mix of concepts seen on greenbuildingadvisor.com, buildingscience.com and the USA new wall info provided by Gregory La Vardera’s site on Swedish framing/insulation - www.lamidesign.com

Asked By Jeff Von Haden | Mar 5 15
2 Answers

With the use of Superior Walls for the basement level, what would be the best interior insulation for a finished basement?

With the use of Superior Walls for the basement level, what would be the best interior insulation for a finished basement?

Asked By RICHARD BOWER | Nov 23 13
0 Answers

insulated slab details for zone 7 walkout

My build is in Kenora Onrtario Canada (zone 7). The basement is a walkout; I need to incorporate a sewage lift station under the floor to pump (shower/toilet/sink and washing machine) water up to my septic
I need to know how to detail the insulation and poly layer under the concrete.
Do I insulate the sides and bottom of the hole the tank (110 gallon) goes into; if so do the joints have to be taped like building an foam box; I can't have the sewage freezing in the tank! Is that even a concern?

Asked By tim brown | Mar 5 15
0 Answers

condensation in (conditioned space)attic.Built to "environmental standards"

I am in need of a (seasoned)Building consultant, familiar with New England climate, able to make an "on site " evaluation in Guilford Ct 06437 for an attic space that was built to environmental standards and is a "conditioned space)--air conditioning,HRVs, etc etc for a client that has environmental allergies, --mold,fabric softener, petrochemical products etc., There is condensation from the attic space, with leakage of water into and onto the first floor after one year.Thank you in advance. We need help.

Asked By herbert suesserman MD | Mar 5 15
10 Answers

Airspace for solar barrier

I am adding a solar barrier between layers of an alluminum roof. The existing roof is over a covered florida room. The roof system has a lower layer that is also the ceiling. The lower layer is connected to the top layer by 3 inch alumuinum I beams. The roof is insulated with porous styromfoam which is noisy when it rains and does not stop any heat penetration at all. Impossible to aircondition! I purchased a solar barrier to place between the layers of room.

Asked By Phillip Ragan | Mar 4 15
4 Answers

24" o.c. rainscreen furring concerns

Getting ready to start a house for a customer, double 2x4 walls, etc. We left the exterior side 2x4 @ 16" oc due to rainscreen furring concerns.

I'm beginning to question whether we can move to 24" oc on the outside wall and use our rainscreen furring 24"oc...?? Furring will be 2x4 KD lumber, mainly because we can get 2x4 cheaper than 1x4 and it's not that much more effort.

So can the furring go to 24"oc and not have problem with the clapboard siding going crazy?


Asked By RMills Miller | Mar 4 15
6 Answers

Insulation around a center chimney -- cape?

How would one insulate around the chimney in the attached pics? Would I start at the ceiling and just put a bunch of Roxul around it? How could air sealing work? Fireblock foam?

Bonus question: Is it too late to double stud these walls?


Asked By stephen edge | Mar 4 15
2 Answers

How can I super insulate, air seal, and vent this space?

This is the top floor of my new to me house in zone 5. Under which is a fully insulated living space of 12 years. So right under that decking is standard 10 in fiberglass..

Asked By stephen edge | Mar 5 15
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