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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
1 Answer

Can anyone tell me which issue has the article on building an under-deck water catchment system?

Since I don't know the name of the article, It's impossible to use the index to find the article.

In General questions | Asked By Carlos Barrera | Apr 6 15
4 Answers

Insulating outside wall for an in-wall toilet

Hello everyone,

I am considering a wall mounted toilet that has the tank in wall. This would be on an outside wall. I am located in New Jersey 20 minutes west of NYC. How much insulation is required to prevent the tank from freezing ?

The tank would be one stud bay away from an uninsulated steam pipe if that makes any difference, I suspect it won't.

Thanks in advance,


In Building Code Questions | Asked By Kurt Kiley | Apr 6 15
3 Answers

Rigid foam over roof sheathing & spray foam interior

I was just reading Martin Holiday's article about rigid foam over roof sheathing and saw that closed cell foam under the roof sheathing was not recommended. Our house has 3" of closed cell foam underneath the sheathing and we were hoping to apply a layer of rigid foam externally in a future roof replacement. What is the reason this is not recommended?

In Green building techniques | Asked By Josh Wimpey | Apr 5 15
5 Answers

Crawlspace vapor barrier product?

The local home centers don't have anything much thicker then 6 mil for poly that I could easily pick up and use for a crawlspace vapor barrier. I have a very small area, less than 100 sq ft, and the proper 10-20 mil thick products I see online have way more material then I need. They also cost quite a bit as well!

I was wondering if it would be a problem to use a EDPM rubber roofing material? I can get a 10x20' roll for $100 and it is 45 mils thick and in stock at the local home center...

In General questions | Asked By William Heiden | Apr 5 15
3 Answers

Roofing - Mechanical seam vs. Snap lock

For a standing seam metal roof which is the better system to install? The Mechanical Seam or the Snap Lock system? Both have hidden fasteners but which system works better?

In Green building techniques | Asked By Peter L | Apr 6 15
2 Answers

Rigid form on interior wall surface

foam insulation on interior side of the wall

In Green building techniques | Asked By Jim Reed | Apr 5 15
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