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9 Answers

Advice needed: Recycled XPS rigid foam

I've located 4x8 sheets of 3" recycled foam board. This is DOW blue board, claiming to be 3" thick.

Should I nab this up for exterior insulation around the foundation? The price seems right and I love to recycle.


In Green products and materials | Asked By Drew Baden | Apr 19 16
10 Answers

Straight line for laying blocks when it's too windy for string?

I'm about to start laying four courses of CMUs for the stem wall of a simple rectangular house's foundation.. It's been very windy here and will continue to be for another few weeks. On the one calm day we had, I projected the string lines for the outer edges of the house downward, drawing lines on the surface of the footing itself so that I would have a straight, accurate line when it's windy, but as I plop mortar down to lay each block in the the first course, those lines will get covered.

In General questions | Asked By Jeff Cooper | Apr 23 16
0 Answers

Please help by answering this survey!

Hi everyone! I'm a high school student that is doing a study on the household efficiency of Solar Panels. If you live in Southern California and have solar panels, please help me by answering this survey! It's fairly quick and you'll be helping a great deal!


Thank you!

In Energy efficiency and durability | Asked By Cynthia Nguyen | Apr 24 16
4 Answers

Best source for long screws?

I'm sure this has been asked and answered before. I need screws in the ~8" range to assemble a rigid insulation/wood sandwich, specifically 5/8" CDX over 6" rigid over 1-1/2" car decking over 4x8 rafters. Many of the screws will land in the 4x8, so could be 8"+, but some will need to land only in the car decking without coming through, and something like 7-1/2" would be ideal. Haven't look anywhere yet, but I know folks here have the answers already.

In General questions | Asked By David Meiland | Apr 23 16
6 Answers

Sourcing High Performance Fiberglass Windows

Hi everyone, I am in Duluth, MN climate zone 7 and am in the process of quoting/sourcing windows. The goal is a net zero house that is relatively small in size at less than 1500 sq. ft. I have one window option for fiberglass from a local dealer (that I know of) and that is Duxton windows.

In Energy efficiency and durability | Asked By Oliver Neumann | Apr 23 16
6 Answers

Ridge Vents - see light?

I was at our new construction home yesterday. It is not yet insulated. I looked up and noticed one small hole where light was coming through. It was at the peak of the roof (runs along the length of the house - it is a ranch). The was no plywood in this area - just synthetic tar paper/shingles could be seen. Our builder said this just where the shingles come together and that no water or anything can get in there. If they put plywood under it, it will wick and rot. He said he could put steel wool there or caulk it but that is not normally what is done. It is normally just left open to vent.

In Building Code Questions | Asked By Carolyn Farrow | Apr 22 16
9 Answers

How best to insulate a 1935 small Cape; is blown in cellulose OK?

I have a 1935 small Cape in the Boston, MA area. We had bad ice-dams the winter before last. There is virtually no insulation (remnants of some exist in the ceiling of the knee wall areas behind the interior walls in those areas; I tore down some that was deteriorated in the knee wall areas when I bought the house 20 yrs ago).

MassSave has recommended blowing in dense-pack cellulose for the walls and either cellulose/netted cellulose w/ foam board or spray foam in the knee wall areas and ceiling.

In Energy efficiency and durability | Asked By Miriam Chernoff | Apr 21 16
9 Answers

Attached garage next to building on posts?

Our house has a 22' x 22' addition that was built (not by us) using posts/sonotube footings. No frostwall. It is, what it is, as they say.

We'd like to build an attached garage next to the addition. So far one contractor has said he won't take the job because he fears excavating for the garage foundation will disturb the posts and without additional support for the addition, we'll have a problem.

I presume that if we throw enough money at this, we could arrange for a temporary support of the addition while we do the work. But that's going to add significantly to the price.

In General questions | Asked By John Gold | Apr 19 16
13 Answers

Ever a good idea to install a powered roof vent?

I know these powered roof vents get a bad rap, but is it ever a good idea to install them?

Such as if the attic floor (ceiling below) has been air sealed. This way the powered roof vent should not be pulling conditioned air from the house, rather it's pulling mainly from the soffits or other areas of easy entry.

Also assuming, the power roof vent is temperature controlled and electric efficient.

Zone 4 represented


In Energy efficiency and durability | Asked By Mark Lancaster | Jun 22 12
1 Answer

What are people using for a capillary break between their footer and foundation wall?

I am getting ready to break ground and of course their are a few minor details I am figuring last minute. One is the capillary break for the footer. I am building in a heavy clay soil that will most certainly have water. I am torn between painting on dry-loc extreme which is most likely cheaper but not really designed for the purpose, and corsella dorken's product delta-footing barrier which is more expensive and has to be ordered. Are there any other low cost alternatives that function well?

In Energy efficiency and durability | Asked By Dillon Vautrin | Apr 22 16
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