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3 Answers

Combining open-cell foam with rigid foam

Hi All,

In Green building techniques | Asked By Steven Dunkel | Dec 5 15
9 Answers

Quonset hut build

Ive been lurking here for some time and have learned a lot. I have purchased a used Quonset hut used and am planning on building it next year. There are no building codes which prevent the techniques I am proposing in the county in which I am building. I would like feedback regarding this design.

San luis valley. Climate zone 7. Money is very tight.

In Green building techniques | Asked By Ben Weeks | Dec 5 15
28 Answers

Two backdrafting appliances and dust — Do I need an HRV?

Hello, I have a problem with my house.

1) My house is probably air-tight

2) My water heater backdrafts whenever the bathroom fan is on. It's probably backdrafted every single morning (windows fog up & I feel the warm air at the flue when it kicks on....it only stops once turning off the bathroom fan).

3) Opening specific windows in the basement relieve the backdrafting of the water heater.

4) There was a lot of dust on a return-air duct that was right above the water heater. Another supply duct near the water heater had rust.

In Mechanicals | Asked By J Pritzen | Nov 26 15
3 Answers

Effect of stack vent, range hood vent, etc. on efficiency

We are building a new home in central IL. If you recall, we have an EPDM roof with 1:12 pitch and 10" rigid foam above the roof deck. The vertical walls are insulted all the way to the roof leaving conditioned space in the attic. The exterior will have 2" rigid foam and EIFS.

In Green building techniques | Asked By Kevin | Dec 3 15
2 Answers

Insulating the attic in a brick home

I am getting ready to insulate the attic of a brick home that was built in the 1950s. I have all the old insulation removed and plan to blow in either cellulose or fiberglass insulation.

Around the perimeter of the attic there is a 1 inch gap between the brick and sheathing on the exterior walls. These gaps appear to extend to the foundation and were not insulated at all and just vented into the attic. I have a couple of questions.

In Project management | Asked By Tom | Dec 4 15
9 Answers

Blower door test

I recently built myself an ICF home, approx. 2,500 s.f. x 2.

I used ICFs from footer to roof and insulated the attic with approx. 10'' of open-cell sprayed on the rocked ceiling. I was diligent about foaming all possible leak points.

I had a blower door test done and was told at 50 pascals it had a natural ach of .04. Does this seem possible?

It seems extremely tight!

In General questions | Asked By Kevin | Dec 4 15
22 Answers

Pros and cons of Grace Ice and Water compared to Tyvek Drainwrap

If applying a WRB under rigid foam insulation, what are the pros and cons of using Grace Ice and Water Shield compared to Tyvek Drainwrap, in terms of protecting the sheathing, serving as an air barrier, difficulty of installation, flashing details, and any other reason you might prefer one product over the other to serve as a WRB? Assuming that the Grace product is more expensive, do you believe that it is worth the additional cost on a 2,000 square foot home in Zone 5?

As always, any advice or opinions are greatly appreciated.

In General questions | Asked By James Timmerberg | Nov 29 15
16 Answers

Total energy efficiency -- ROI and what else to do


Very much appreciate everyone's feedback. I would like to give a quick overview of the improvements I have performed to my new (to us) home and look for feedback but additional DIY improvements to save energy.

In Energy efficiency and durability | Asked By Justin Brown | Nov 17 15
9 Answers

Insulation payback

A co-worker of mine is planning his new house. I have been offering suggestions on insulation. His architect has commented that the payback is too long for any insulation other than fiberglass. How do you respond to that?

In General questions | Asked By Scott | Dec 3 15
7 Answers

New home shell

Exterior walls
2x6 studs
5/8" exterior plywood sheathing joints taped
Benjamin Obdyke house wrap 1 MM drainage gap
Celect cellur exterior siding
Interior of 2x6 studs has 1" thick high density EPS with 1x3 strapping over for thermal break
Enclosures to seal electric boxes
Roxul mineral wool insulation

Will this give me a sound exterior shell for Delaware Zone 4 ?

In Energy efficiency and durability | Asked By Edward Serafin | Dec 3 15
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