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9 Answers

How much of a gap should I allow in exterior plywood sheathing to allow for expansion and contraction?

Thank you to everyone who has posted and responded to related questions and gotten me to the point where I can more or less ask this question in an intelligible manner.

Asked By Joel Fyke | Jun 24 17
7 Answers

Cheapest way to build net zero house?

Hi. I have some questions about building an affordable net zero energy house. I will present a basic outline of my plan, and then ask some questions. In addition, I welcome any comments on any parts of the plan which could use adjustment.

Note: I am not a professional and only know what little I know from browsing these and other websites.

Asked By user-6877304 | Jun 28 17
2 Answers

Capillary break product that will soak into concrete?

I asked a before about the need for a capillary break between the footing and the poured 5,000 lb. basement wall. I was told that I still need one. My foundation company has documentation that states it isn't need for 5,000 lb. concrete. They agree to put a capillary break in on top of the footing if it will soak in. They said one customer put Thompsons water seal on.

Is there a good product that would serve this purpose? Hopefully readily available.


Asked By Jim Sweazey | Jun 28 17
10 Answers

Panasonic WhisperValue DC fan and TRB transfer box - anyone using these in the field yet?

For a while now I've been considering different ideas to distribute the air from my mini split to bedrooms when the doors are closed. I just noticed that Panasonic recently came out with a new DC motor version of their 3 3/8" deep WhisperValue fan, with selectable speeds (50/80/100CFM) and pretty low sone (noise) ratings.

They also make this transfer box that's designed to fit this fan (google Panasonic TRB -- I can't link anything or the spam filter gets me).

Asked By Nick Welch | Jun 27 17
0 Answers

Rigid foam on top of studs

I'm currently in zone 5 redoing a brick ranch home. The wall from the outside to inside is brick, plywood, black sheeting, R-11 and drywall. All of the drywall is down and wall cavities are exposed. The customer wants to use R-15 Roxul insulation and add rigid insulation on top of the studs with taped seams and drywall over that. I know some people do that but not sure which type of rigid foam insulation to use in order to prevent moisture inside the wall. I think we would like to use 1" rigid foam to make sure we can attach drywall correctly.

Asked By tkaj | Jun 28 17
11 Answers

How to prevent moisture/condensation in building prohibited from using insulation?

I am building a small cottage that by code is prohibited from using any insulation (so as to prevent its use as a full time dwelling). It is a simple wood framed structure with drywall interiors that has A/C but not heat and will be used only in the summers (northeast US climate).

Asked By bsgsjkbn23450 | Jun 28 17
2 Answers

Pros/Cons of upgrading to 5 stage heat pump from 1 stage?

My residence currently has a Carrier 1-stage heat pump system. Other HVAC components include: LifeBreath HRV195 balanced airflow ventilation unit; Honeywell DR120 bypass return air DEhumidifier; and a bypass activated carbon & HEPA air filtration unit. Each of those components have their own integral 1-speed air fan. Dealing with the different cfm created by each of those components makes it a challenge for my HVAC service company to achieve "balanced" airflow for the HRV and keeping the HVAC system static pressure within specifications.

Asked By Terry Sopher Sr | Jun 28 17
0 Answers

Window sill pan question

Hi all,

I am about to install my windows and will be making my own sloped sill pan. I will be using bevel cedar and screwing on a thin back dam as well. Over this, will go the flashing tap.

Regarding the back dam, should it go behind the window (interior side) or under the end of the window? I would think it would be best practice to have it go behind the window. Only downside I can see is making interior taping more difficult.

Please see pictures on which method I should use.

Thank you!

Asked By Tommy87 | Jun 28 17
12 Answers

Does the insulation on this wall make sense?

I live in Madison WI and am renovating my 1927 house. I have stripped the outer walls to the studs and shiplap and have been trying to figure out the best insulation scheme. The constraints are 1. in Madison they really want plastic on the inside, and 2. because of architectural details I can't put more than 1 inch rigid insulation on the outside.

Asked By user-6832947 | Jun 27 17
3 Answers

Attic insulation advice needed

First off, GBA is a fabulous resource for us, as we plan to build our “final home” in Asheville, NC. Climate zone 4. Our home will be a 26’ x 44’ ranch with a partially exposed, walk out full basement. Standing seam metal roof, scissor trusses, Zip system wall and roof sheathing, stucco exterior, 3’ eaves and gable ends. We will do a LOT of air sealing, greater than required insulation and high quality windows. The mechanicals and ERV will be in the basement (not in the attic).

Asked By Nancy Broadbear | Jun 28 17
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