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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
3 Answers

Metal Roof Fasteners backing out

Hi Martin Holladay.
I was reading Fine Homebuilding March 2015 and found the article about through fastened metal roofing.
A friend of mine was asking about screws backing out of his roof and I was curious about your opinion about the cause and the fix.
His house is in an area that receives 1-3 feet of snow per winter. Snow usually stays for several weeks.
The metal roof has screws that have backed out.
I was thinking the snow and ice may snag against the screw during melt and movement over several seasons, working the screw out of the roof and structure.

See attached picture.

In Energy efficiency and durability | Asked By Franklin French | Apr 4 15
21 Answers

2/12 cathedral roof replacement


I have a shingled 2/12 roof that needs to be replaced it is a cathedral ceiling. It has no dormers or right angles to it, the size is about 40' by 20'. I am in Vermont so i have serious ice dams which i would like to minimize but heres the catch i am not looking for the 15k to 30k option. I am looking for the most reasonable balanced option under 10k. I have received a few quotes.

1. Strip roof, ice and water shield, architectual shingle ~5500k

In GBA Pro help | Asked By mark kessler | Feb 23 15
1 Answer

How to cover and insulate a floor up on 4' piers or posts to keep the weather out, heat in, and the government men happy

1,236 sq ft., above ground on piers.
One story high, 4 feet off the ground, like a home on the coast, with no walls around the bottom sides.


In Green building techniques | Asked By Jon Uhrick | Apr 3 15
4 Answers

New Construction Insulation

I will be building a 3,600 sq foot house in Salt Lake City. All space will be conditioned. The basement, main, and upstairs are each 1,200 sq feet. The roof has 2x10 rafters, is 6/12, and will be standing seam metal.

I had some energy modeling done and the engineer recommended:

4 inches of EPS under slab
2 inches of XPS on the exterior of the walls
2 inches of Polyiso on the exterior of the walls
4 inches of EPS on top of the roof

In Energy efficiency and durability | Asked By Matt Frieda | Apr 3 15
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