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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.

thanks

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?

http://www.wanessa-sue.com/

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

Hey,

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
4 Answers

Heat Loss and Manual J - PHPP and/or HRAI Manuals?

After looking into having heat loss/gain analysis done on my new house build I'm not surprised to see the costs coming in at $500 and up.

I am a Mechanical Technologist and have no problem with technical topics and math. As such, I have a hard time justifying paying other people when I can educate myself and learn how something is done. I generally prefer doing things myself anyway, that way I not only fully understand what's going on, I also know the job is done right.

In Mechanicals | Asked By Lance Peters | May 16 17
17 Answers

Still Grinding - Uninsulated basement and minisplit problems

It's been about 1 year and 10 months since I started building my house and I'm still grinding. Doing the board and batten siding mixed with cedar is taking some time. Especially since I'm doing it mostly by myself!

In Energy efficiency and durability | Asked By Jimmy Nguyen | May 9 17
6 Answers

New addition with closed cell in rafters on top of current roof?

Hi,
We live in a coastal town in MA and just started an addition on a 1940's house. Currently have a simple sloped roof with blown in cellulose on floor. Two gable vents on either end and a few roof vents that we put in as well. The addition will be two stories and be a 'roof on roof' per the architect with a cut out to allow for electric/HVAC to be brought in from the current roof (HVAC is in this unconditioned space currently). The plan is to re-roof the entire house when the addition is put on. The addition will be unvented and have spray foam in rafters.

In Energy efficiency and durability | Asked By eoren1 | May 16 17
13 Answers

ERV help

Here are the details on our house build:
1792 square feet plus full basement, zone 5. 3 bedroom, 2 bath. 4 people in the house

In General questions | Asked By Michael Brackett | May 15 17
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