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4 Answers

Foundation question: Slab on grade or monolithic?

I am going to build a small 12 x 16 Timber Frame house in the Intermountain West - Zone 6. I attached a rendering. One question I have is about the foundation. I think I am confused about the terminology that I hear. Would it be preferable to do a monolithic slab or a slab on grade with a stem wall? I know there are lots of details here and in Lstiburek's Building for Cold Climates but I'm wondering what a pro might recommend (no basement or crawl space).

In Green building techniques | Asked By John Brown | May 17 17
13 Answers

R-24 spray foam enough?

Hi there,

In Energy efficiency and durability | Asked By User-6848033 | May 18 17
4 Answers

Advice on Slicker Max rainscreen?

I am looking at a wall comprised of 2x6" frame, cellulose in the cavities, Huber Zip system exterior, 1.5" Poly, Slicker Max Rainscreen 10M, and then nailing cedar shingles directly through rainscreen and foam (approx 1 3/4").

My Builder does not want to deal with putting up 1x4" nailers every 5" to hang shingles from, so thinking rain screen will give shingles ability to breath. Depending on cost this might be an alternative.

Also not sure if this will meet code on Cape Cod with wind code, or if hanging shingles in this manner would work. Thanks.

In General questions | Asked By Steve Kreisher | May 18 17
18 Answers

Protecting Redwood siding

I have moved into a house with unpainted vertical channel-rustic redwood siding. Unfortunately, some of the siding extends down to within a few inches of the ground. In spite of there being a 2-foot gravel perimeter around the house, and in spite of there being a 2-1/2 foot eave overhang, rain splashes against the lower portion of the siding, and after 35 years it is showing signs of decay.

In General questions | Asked By Jack Woolfe | May 15 17
18 Answers

How important is a thermal break between a house foundation and an attached garage foundation?

Our footings were poured today for a new house and attached garage. The walls of the basement foundation (9') and garage foundation are scheduled to be poured next week.

Looking over the plans, our concrete sub is worried about the 7" thermal break between the basement and garage foundations (no physical connection) as currently drawn on the plans. The separation is there in order to allow us to attach 5" of Roxul Comfortboard 80 to the basement foundation (we'll be doing the same for the whole exterior perimeter of the basement foundation).

In Green building techniques | Asked By Eric Whetzel | Dec 2 16
16 Answers

Rookie question about Roxul Comfortbatt insulation

I am insulating the attic ceiling. My house was built in 1907 and has 2x4 rafters spaced around 22 inches apart with some variation in the distances. I purchased 23" Roxul Comfortbatts. The question is can I compress 23" into my 22" space or do I need to cut an inch off the batt for optimal insulation?

In Energy efficiency and durability | Asked By Leda Felicio | May 17 17
3 Answers

Strata International

I've come across a new to me building technology which is being utilized in the Phoenix area. It is essentially the inverse of ICF. 8 inch EPS core for the walls and 12 inch for the ceiling with both sides finished in a shotcrete like concrete product. The system comes from Strata International (strataus.com).

In Green building techniques | Asked By Jeffrey Savage | May 17 17
3 Answers

Insulation and R-values

I live in Edmonton, Alberta. I am remodeling a home and trying to figure out the R-value I want in the walls and attic. I have seen recommendations in building codes and on several websites.

I am trying to figure out the difference in efficiency and cost/savings of different R-values. Any charts that explain this would be helpful.

Please let me know if you know where these charts can be found.


In Green products and materials | Asked By User-6846735 | May 17 17
5 Answers

R-30 Panel - Wanessa-Sue ?

This manufacturer is claiming an R-30 panel and no thermal bridging. Looking at the design, the steel goes from exterior to interior, so this would be a thermal bridge. Anyone heard of or researched these panels?


In Energy efficiency and durability | Asked By Peter L | May 16 17
27 Answers

Fujitsu Heat Pumps cause weird sound in breaker box and exhaust fan


Weird issue I'm experiencing and this obviously isn't an electrical forum but I wondered if there was enough mini split installations here that someone else may have experienced this...

The weather is turning warmer in Zone 4A so I am turning out my Fujitsu mini split heat pump A/C for the first time since our house has been under construction, and I noticed a weird sound coming from my whispergreen bath fan. It is hard to describe, but it is like an electrical hum similar to a flourescent light ballast. The sound gets louder when you actually turn the fan on.

In Green products and materials | Asked By Clay Whitenack | Apr 17 17
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