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20 Answers

Ramblings on thermal mass, AC and window fans

This is isn't really a specific question so feel free to offer random thoughts

In Energy efficiency and durability | Asked By Alan B | Jul 10 16
15 Answers

Fluid WRB at big box stores?


I am interested in building a workshop/studio 16'x12'x12' and am interested in using a WRB. I read the wrb in a can article on this website and lots of other information on the subject. When I look at the mentioned products, they do not seem to be accessible in local stores or something that a non-contract professional can find. Is there a Home Depot or Lowes type solution? This studio will be assembled in the order of a 2x4 framed, OSB sheathed, fluid WRB, drain wrap, 3" XPS and seam sealed, rainscreen, fiber cement.

In General questions | Asked By John Haller | Jul 21 16
5 Answers

Tying in Addition Roof

I'm having trouble finding definitive answers on how to tie in my additions roof.

The home is a basic ranch roof, no dormers on the addition, just a straight roof. I'll be tying the addition into the gable end of the existing home using the same roof pitch and truss design for the most part.

-Should I just snap a line and cut the eave, including shingles and fascia right off? I know the fascia will have to go to get the new truss in at some point.

-Do I need to weave in the plywood to the original roof if there will be a new truss sistered up to the gable?

In General questions | Asked By Mike M | Jul 20 16
7 Answers


I see GBA is being attacked by spam. I don't want to give this more attention than it deserves, but can someone tell me why this occurs? What benefit is there to whoever fills the Q and A with this content? If my question is some way aids them, please delete it.

In General questions | Asked By Malcolm Taylor | Apr 21 16
1 Answer

Insulating a sloped ceiling

I have a 1.5 story home built in 1900 in southern NH. Minimal insulation on attic floor and some stuffed into the sloped ceiling from the attic. The insulation contractors that have looked at it want to dense pack the bays on the sloped part with cellulose. One said he could flash it with spray foam to seal it first, then dense pack. I have read that insulating with no venting is a bad idea. I understand without ripping the drywall down, it would be very difficult to insulate properly and add vent chutes.

In Energy efficiency and durability | Asked By Frank Mengler | Jul 22 16
2 Answers

Replacing insulation in basement

Hello, I have a 3 year old basment with 8ft concrete walls that was finished with 2 by 4's that are about 1/2 inch off the concrete wall and fiberglass batting was used as insulation which I don't believe is the correct material. If i want to replace this should i go back to the studs and perhaps do a spray insulation or is it best to take everything out and start afresh. At this point i do not have any mold/smell issues but also think it could just be better insulated. I am in zone 5/6, right on the edge. Thank you.

In Green building techniques | Asked By J D | Jul 21 16
7 Answers

How should I heat my water?

Hi there. I'm just starting a major renovation of a two story studio space attached to our detached garage to be used as a studio and sometimes guest house. We're adding water and septic to the house, and I'm looking for ideas on the best way to get hot water. We'll only have a single bathroom with shower, and a small wet bar sink on the same wall as the bathroom, so there are no long pipe runs. Usage will be infrequent but once in a while fairly aggressive if we have guests there who need to take multiple back-to-back showers.

In Mechanicals | Asked By Curtis M | Jul 17 16
2 Answers

Exterior and interior foundation insulation crossover

Hey All,
In the process of adding exterior insulation to foundation wall but am having an issue in a spot in the backyard where there is a new patio and front yard with a deck. My wife would rather i not rip out a brand new patio and new deck to insulate the foundation. So i was wondering if it would be better then nothing to in those areas put the insulation on the interior of the block and just have an overlap of say 10 feet where there is both exterior and interior insulation?


In Energy efficiency and durability | Asked By Chris King | Jul 22 16
4 Answers

Will this rainscreen assembly work for this application?

I am building a tiny house on wheels and I wanted to have a rain screen included. I would just like to use a mesh product for ease of installation and fastening options later.

I live in southeastern South Dakota. I will be using a 1" standing seam metal roof with a 5/8:12 pitch.

I have included a rough sketch and was wondering if it would work to have a continuous and connected wall and roof rain/vent screen?

In General questions | Asked By Damon Beck | Jul 21 16
7 Answers

Solar Water Behind a Window

First a quick back story: I live in Halifax, Nova Scotia, which to my knowledge is zone 5...? I'm getting condensation on my cold water pipes, where the pipes first enter my house from my well. In another question about this issue, Charlie Sullivan was kind enough to offer a suggestion of using a drain water heat recovery unit to preheat the cold water. Which, really is a great suggestion as it's 100% passive.

In Mechanicals | Asked By Calum Wilde | Jul 21 16
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