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2 Answers

Avoiding a ledge in a basement


Let me start by saying I am not a builder so pardon my explanation. I am located in Nova Scotia, Canada. I am looking to finish my basement and I want to avoid having the basement ledge I commonly see. We have a step down foundation so all of my walls have an above ground section that has been drywalled, vapor barriered, and has fibreglass insulation and a below grade section with exposed concrete. My contractor recommended building a wall in front of this so we could avoid the ledge.

In Green building techniques | Asked By Jason Keddy | Nov 4 14
7 Answers

Climate Zone 6: Low-slope warm roof materials / assembly

I am designing a large mono-pitch shed roof in Climate Z6. The slope is 1.5 in 12 or about 7 degrees. A ventilation space seems impossible due to the scale of this roof plane. 60 feet sloping up and about 25 feet wide. I would like the finished roofing to be standing seam metal as the roof is visible from various vantage points on the property.

It my understanding that we will need to install a high-temp waterproof membrane like Grace Ultra over the entire roof sheathing to prevents leaks. This means the roof assembly is only able to dry to the inside.

In Energy efficiency and durability | Asked By Meri Tepper | Oct 29 14
3 Answers

I am considering a double wall construction

I am planning to build a house in Charleston, SC (Hot -Humid Climate) and would like to get as close to Net Zero as possible. I think mini-splits will work but dont know if double wall construction is the way to go. Any help would be appreciated.

In Energy efficiency and durability | Asked By Rick Fetter | Oct 30 14
0 Answers

Attic insulation options

Hi all,

This is about my primary house attic space. At some point I am going to finish half of it off. Here is a pic of the space:

Basically when you get to the top of the stairs, what is in front of you is what will be finished. Where the HVAC is located will be left "attic storage". This will give me roughly a 20x20 space.

In General questions | Asked By Joe Watson | Nov 3 14
10 Answers

Paperless Home Design-Build

I don't know how many are aware that over the past decade or two the aircraft/auto and some other industries have gone to paperless (no blueprint) designs. The design is built and inspected to 3D datasets, or DMUs(Digital Mock-up Units), some of which, but not all, interface to CAM(Computer Aided Manufacturing), mainly auto-fastening, CNC machining, rapid prototype type operations.

In Plans Review | Asked By Terry Lee | Nov 2 14
3 Answers

Solar gain tradeoff?

While the topic of solar gain via south-facing windows recently
came up in the "Martin's PGH manifesto" thread, I'm not going
anywhere near that flamewar with this question even if it's
peripherally relevant. The question concerns how worthwhile
it actually is to open my reflective shades on a sunny winter
day, and/or if there's a critical-point outdoor temperature
where increased radiative/conductive loss going *out* would
be insufficiently balanced by solar energy coming *in* and

In Energy efficiency and durability | Asked By Hobbit _ | Nov 3 14
6 Answers

Double wythe CMU vs. Thermomass

After living in Europe for several years I have become a fan of concrete. I build in the Southeast and have mainly used concrete commercially and as stem/foundation/retaining walls and for slabs in residential.

In Green building techniques | Asked By leo kloop | Oct 22 14
1 Answer

Can loose-filled cellulose insulation be dense-packed, or does it have to be removed and reinstalled?

I hired a company to fill my walls, they used the 2 hole method and loose filled the walls, from what i have read the R value would be comparable but it will probably settle over time and have a higher air infiltration rate. I checked the contract and it does not actually state dense packed even though i am sure i requested it when i was getting quotes. Stupid me. I don't think they do dense packed, the installer does not know the method for dense packing, or the density of his installations and their truck probably could not put out the pressure even if they had the right hose for it.

In Energy efficiency and durability | Asked By Alan B | Nov 4 14
5 Answers

Condensate moisture around window frames

I am in the process of foaming and taping the spaces between my interior window frames and boxes. I have noticed that after sealing the gap with tape (after foam has cured) that I begin to have slight moisture on the tape surface only on the bottom section of the window frame. I didn't notice it after I foamed and before I taped; only after taping. I have also noticed it under my exterior door, on the interior side, despite proper sealing of the door frame on the sill (It's certainly not water from the exterior making its way in).

In GBA Pro help | Asked By Matthew Michaud | Nov 2 14
7 Answers

Foam insulation question for 100-year-old brick home

The attached illustration depicts the current condition of my wall. The plaster and the lathe is currently removed from the wall.

What I'm thinking of doing is spraying 1/2 to 1 inch of closed-cell foam along the inside of the stud and on top of the sheathing, which will serve as a vapor barrier. The remaining space will be filled with fiberglass insulation, and topped by 5/8-inch of drywall and latex paint.

Another option would be to spray low-density insulation between the brick and wood sheathing by drilling holes in the sheathing.

In Green building techniques | Asked By Wes Leland | Oct 30 14
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