Community: Green building techniques

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19 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
10 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
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
1 Answer

Roof vs. ground gutters

I'm going to be working on my grandfather's house soon to deal with moisture getting into his poured foundation. The 1940's ranch house is in Central Maine in heavy clay soil. The foundation has multiple hairline cracks in it. I think part of the cracking is due to the expansion of the clay and/or hydro-static pressure when it rains. I read the article on this site about ground gutters and I'm intrigued by the idea. I question if they are going to be more effective for a couple of reasons:

Asked By Andrew G | Jun 28 17
1 Answer

Insulating an exposed cement wall

Zone 4 NC build, on a steep slope which requires some foundation trickery. One spot I have a question about is the exposed portion of cement wall that is between lower level living space and the air space beneath the garage(garage is on steel beams). See the attached pics. The plan was to do 2" foam board around the entire lower level cement foundation areas(inside). Will that be enough in this spot when you account for the 2x4 wall + the additional insulation inside that wall or should I do thicker foam along that wall since it will forever be exposed to air?

Asked By Kevin Spellman | Jun 25 17
3 Answers

Air barrier between garage ceiling and living space above

I'm planning to build a "pretty-good" house in climate zone 5b, just south of Denver. My house has an unheated but well-insulated garage below a Great Room above and I am trying to figure out the air barrier. Floor design is, from top to bottom:

1) Laminate floor finish
2) OSB floor sheathing
3) 11 7/8" TJI w/ cellulose insulation
4) 1" EPS for thermal bridging,
5) 1/2" drywall installed using airtight drywall technique.

Asked By Lawrence Martin | Jun 24 17
2 Answers

Conditioned or unconditioned crawl with mini-splits

I am looking at putting a mini-split into a new home but can not seem to find an answer on how or if I should condition my crawlspace. I know crawls aren't the best route but I don't have the extra $17k to do a basement and a slab isn't an option. So can I build the crawl as a conditioned space without the hvac runs keeping it climate controlled or how should I go about this? I'm willing to put another head in the crawl if that's what needs to be done to make it work.

Asked By DG Builder | Jun 23 17
8 Answers

Rigid insulation beneath floor on shed

Hello,

First time posting and would like to thank you in advance for at least taking the time to read this.

I am building an insulated shed/writing studio for my wife. Looking to make it 12'x8' and was thinking of building it on concrete blocks with 2"x6" studs for the bottom frame. On top of that I was planning on 2" rigid insulation followed by plywood then flooring. Will I be able to put the sill plate on top of this and drill through to the 2"x6"'s? I haven't worked with rigid in this context before.

Putting it on blocks seems the best option in case we wish to move it later.

Asked By Allan Manley | Jun 22 17
25 Answers

Sealing bottom plate to slab

My framer says that Sill Seal does not do a good job. I am inclined to agree with him. He is recommending a bead of liquid nails. I have been looking for real information. Certainly by now there have been some test run to measure the efficacy of various products and methods. And a new home slab is not a laboratory. How well does this or another product stick to a slab that has been wet and muddy?

Asked By Hugh Stearns | Aug 28 13
18 Answers

Attic conversion - modified cut and cobble

I would really appreciate any assistance can provide me with my unvented attic.

I have a modular house in climate zone 5:

The sealed plans for the house specify attic truss construction:

I somehow ended up with something more like this:

At any rate, I'm going to restore the structure to the original plan. As you can see, the roof doesn't feature a ridge. The pitch is 9/12 and the rafters are 2x8 (truncated to 2x4 at the top, but I'll fur that part out to 2x8).

I'm planning the following roof assembly:

-synthetic slate tiles (existing)

Asked By Ben C. | Jun 17 17
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