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3 Answers

Insulating radon-mitigated crawlspace floor

I finally have solve the radon problem in my house and sitting pretty with 0.8 average. Also very happy that formerly "unvented yet might as well be", dirty, and damp space is now so clean, I only walk in my socks there.

That all said, walls I am insulating with polyiso (two layers of 1.5"), rim joist I am going to spray with closed cell, when space becomes warm enough. But it leaves the floor uninsulated.

In GBA Pro help | Asked By Apollo S | Apr 8 15
5 Answers

Please review this window retrofit and provide feedback

Can I get feed back if the pictures tell the story of a good window install.


In General questions | Asked By Alexander Sanita | Apr 8 15
8 Answers

I need assistance with window/door install with 4" foam

I am looking for some direction on installing windows and doors. I have 4" exterior EPS on a 2x6 walls

The current plan is to build 5/8" plywood boxes (I believe they are called Dewey boxes) to get the nail fin of the window to the same plane as the furring strips that the foam and the siding will be attached to.
I am sure its been covered but searching Dewey box got me 0 results so I wonder if someone could point me in the right direction?

Tim (Kenora ON Canada zone 7)

In Green building techniques | Asked By tim brown | Mar 28 15
14 Answers

Using recycled rigid foam

I'm considering using rigid foam on the exterior of my roof. Cost is of course a big concern with this approach. I'm found sites online that sell recycled rigid foam. Apparently, it is often recovered from commercial buildings and shipping containers.

I read one post on the site that caution against using foam that had been degrade during freeze/thaw cycles. Are there any other issues to look out for? Have anyone tried the "recycled" approach? Is there a reputable source for material? Any lessons learned you folks could share would be greatly appreciated.

In Green products and materials | Asked By Steven Knapp | May 10 13
3 Answers

Is there a humidity calculator out there?

I live in a leaky house, the inside humidity tracks the outdoor humidity with a lag and temperature adjusted, but i want to be able to input an outdoor temp and humidity and calculate what the indoor humidity will eventually become at 20ºC (theoretically of course).

Basically i want to know what the resulting humidity would be at an input temp and humidity if that air was raised to 20C

I know the outdoor will eventually change before the indoor catches up but it would be useful to me.

In General questions | Asked By Alan B | Mar 15 15
2 Answers

What is the best material for the underside of a porch?

Currently the underside is bead board. After this winter in the Northeast it split from ice dam buildup and 2' of snow sitting on the outside overhang 8' by25'. The style of the house is a New England farmhouse. I understand their are two thickness' of wood beadboard, PVC. I'm a little reluctant to use the wood because of possible moisture. The orginal was but up in the 20's. Replaced with new in2014. The thin wood type.

In General questions | Asked By John Spears | Mar 23 15
6 Answers

Yet another minisplit sizing question

I'm building a new home in Washington state (Seattle area, Marine 4C) and it should be fairly well built as I'm keeping the design simple, with rectangular dims and minimizing penetrations in roof/wall/floor. The builder claims "energy efficient" methods but they all do. Washington does require fairly progressive standards and a blower door test is standard fare. I won't have results until the building is done and I'm planning for my mini-split now.

In Mechanicals | Asked By Kevin Haskins | Apr 6 15
6 Answers

BSC Task 11.4 cellulose product results

I'm currently working out the details for insulating the walls of my 1.5 story home, and I'm pretty settled on dense packing the walls with cellulose. (For reference, the walls are 2x4 with plaster/lath finish, and metal siding over what I believe is OSB sheathing on top of spaced plank, with a paper thrown in the mix on the exterior. As well, the home is in climate zone 5A.)

Along my research I ran across this paper which discusses results of 10 different loose fill cellulose products, and it notes that some are better than others due to contaminants and material consistency. --

In Green products and materials | Asked By Nathan Schulte | Apr 3 15
9 Answers

Where do I put the vapor barrier in a double stud wall with pluming penetrations?

So if you have been following the site for a few weeks you may have seen some of my previous questions. Some have sparked a lot of debate and some I left out too many details to get any good input. However, I am back with another question. First, my wall assembly. I'll have a double stud wall with OSB sheathing (except north wall where I'll use plywood). Outer wall will be the structural wall and since it will be two stories I'll be using 16" centers with 2x4's. I'll have a 3.5" gap and then another 2x4 wall.

In Energy efficiency and durability | Asked By Andrew Bennett | Apr 6 15
2 Answers

Thermax sturdiness?


In Energy efficiency and durability | Asked By Chris Simmons | Apr 6 15
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