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14 Answers

Using a 'whole house like' fan for cooling

Have read your info on Whole House Fans, grew up with one and would like to use the concept. Would you comment and correct my thinking?

In General questions | Asked By Ron Kliesch | Aug 25 15
2 Answers

What is your opinion of the CERV HRV system?

Looking to add an HRV to a new home plan, 2500 sq.ft.

Concerned with humidity levels in Massachusetts. Very humid summer. Dryer winter. House will be close to net zero.

In GBA Pro help | Asked By Joseph Isherwood | Aug 26 15
4 Answers

Advice needed to insulate an existing block wall from the exterior

The local parish hall has a 40' x 44' addition with exterior walls of 8" concrete block and a bow truss roof/ceiling that was built in the 60's. On the interior, there is no additional wall build-out or insulation, just exposed block. We are planning on insulating the exterior walls and adding blown in cellulose to the existing fiberglass roof insulation after air sealing all penetrations.

In Energy efficiency and durability | Asked By Jon Michael Wyman | Aug 25 15
2 Answers

What can I do to address a condensation and mildew issue on a cathedral ceiling?

Our house is 35 years old and has a cathedral ceiling in the living area located in the center of the house. We have never had an issue with the ceiling until about 5 years ago. Condensation develops during the summer months on the ceiling and ultimately results in mildew that spreads across the entire ceiling. We live in LA and the heat in the summer is in the 90s during those months. Approximately 8 years ago we replaced the roof on the house, using the architectural shingles and removing the power vents and replacing them with a ridge vent system.

In GBA Pro help | Asked By Susan Cochran | Aug 24 15
5 Answers

How to get a Pretty Good House built?

Designing a Pretty Good House (PGH) is easy. Just spend a year or two reading at GBA, pay for a GBA Prime/Pro membership to get access to detail drawings, and bam, you're done. Kinda, not really, but go with it for a minute. So now that you've designed it, how do you get it built? This is the one article that I don't remember being specifically addressed.

In Project management | Asked By Andrew C | Aug 24 15
13 Answers

Keeping HVAC inside conditioned space

We have just started construction on my new house. I want to keep the HVAC inside the conditioned space for energy efficiency. The crawlspace will be conditioned and we are using open web floor trusses on the second floor to accommodate the ducts for the second floor.

In Mechanicals | Asked By Michael Geoghegan | Aug 22 15
2 Answers

Yet another basement question

First, let me just say THANK YOU for this wonderful resource. The advice and analysis you give here is priceless and it is just a pleasure to read through the posts here.

In Green building techniques | Asked By Corey Vanhove | Aug 24 15
2 Answers

Insulating a porch roof to create a four-season living space

I live in southeast Nebraska and I would like to turn an east-facing 19 by 8 ft. already enclosed porch with a concrete floor into a 4 season living space. there is no structure above the roof.

I don't see a way to vent the roof and would like to know if I used R-30 insulation and Reflex-it vapor barrier , with the proper dead air spacing and sealed it so very little if any water vapor could escape to get to the under side of the R-30 insulation , if I would be creating a problem with condensation.

In General questions | Asked By Rick Eberly | Aug 25 15
17 Answers

Is it advisable to use nail base insulation panels over a roof insulated with closed cell spray foam?

We are renovating an old railroad station, turning it into a residence and are gearing up to put new roofing on the building. Built in 1888, the building has massive overhangs on all sides and the rafters are mostly 2x6s with 4x6s spaced about 8' apart supported by large brackets. We had planned to use closed-cell spray foam insulation in order to get the maximum r-value in the relatively shallow rafter bays. Also, we want to maximize the available head room in the second floor rooms. The underside of the roof will also be the ceiling with t&g beadboard installed directly to the rafters.

In Energy efficiency and durability | Asked By Jodi Gunderson | May 29 15
6 Answers

"Cycling" ductless mini-split

I'm working on my wife re: her dislike for the appearance of ductless mini-splits, but I have a question regarding their operation.

In Mechanicals | Asked By Brad VanVickle | Aug 23 15
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