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6 Answers

Does this setup seem sufficient?

After reading many of the articles and comments here, I've been inspired to try and build Passive House insulation and air tightness.

I'll share what I'm thinking so far with the hope that maybe you can direct me in any way. Not necessarily trying to get Passive House certified, but would like to build airtight anyway.

Region: west mountains of Dunlap, TN


In PassivHaus | Asked By Edwin Perdomo | Nov 23 15
14 Answers

Connecting masonry cavity foam insulation to windows and running services in CMU hollow cores


I live just out of Melbourne in Australia. For reference, our climate zone is Cfb (temperate, without a dry season and with warm summers). Annual HDD (Farenheit, with base 65 degrees) is 2,838 degrees. Annual CDD is 450 degrees. It very rarely goes below freezing temperature.

In General questions | Asked By George | Nov 23 15
8 Answers

Best roof assembly on a budget?

Thank you for your website and for the exceptional information available here. I am an active student of GBA and a big fan.

I live in Central East Texas, Hot Humid, and am in process of remodeling a mid-century modern home with low sloping roof lines: 1.5/12 to 3/12. Essentially the entire home and roof assembly will be a vaulted ceiling setup since the interior ceiling is the actual roof deck. Roof is about 50 square.

In Energy efficiency and durability | Asked By Chris | Nov 24 15
17 Answers

It seems the trap was left out on the shower drain on a slab house. Any way to fix that short of a jack hammer?

My son just moved into a slab house on a septic system. After using the washing machine, they noticed a sewer smell coming from the shower drain. They had showered the day before. If there is indeed no trap between the shower and the septic tank, is there a solution short of a jack hammer? Perhaps a valve? The drain is a trough style with a 1.5 inch opening.

I told him that maybe the washing machine had emptied the trap. There is a vent for the washing machine and behind the shower.

Is there a simple way to tell if there is a trap? Thanks

In GBA Pro help | Asked By Tooger Smith | Nov 10 15
10 Answers

Adding insulation to a 1930s home with a slate roof

Location (New Jersey)

In Energy efficiency and durability | Asked By David Adler | Nov 23 15
10 Answers

Closed-cell spray foam between studs with various exterior continuous insulations

I want to make a few questions very explicit to get some good solid answers.

In GBA Pro help | Asked By Patrick | Nov 19 15
5 Answers

Leftover mineral wool shavings

I have about 150 1.5" thick pieces of 16" x 47" mineral wool insulation. From a prior post I mentioned I was going to try adding it to my attic as I began insulating it (new construction). However, I just got my 12" thick fiberglass batts and began installing them between the trusses. The insulation is very airy..or fluffy. If I put these mineral wool scraps on top of the fiberglass running perpendicular.. I actually see the fiberglass shrink some from the weight! It compresses a good inch or two. I wonder if I am doing more harm than good. I know fiberglass needs to be loose.

In Green products and materials | Asked By Nicholas C | Nov 24 15
6 Answers

How should I insulate my exterior walls?

I live in zone 4a, northern Virginia. My house is a single story, 2x4 exterior walls, no plastic wrap on the interior, no sheathing on the exterior, no house wrap on the exterior, and the exterior siding is RB&B board. The house is 40 years old and has just 40 year old batting insulation with siding. I want to spray foam, from the exterior, but one person says do not use closed cell because it is too hard to cut smoothly and water could settle in any uneven places, the next person says to only use closed cell.

In Energy efficiency and durability | Asked By Michael | Nov 23 15
9 Answers

Why will our heat pump not warm the whole building?

Our office has complaints about the building we work in -- it will not get warm. We have an old boiler, but when we renovated in the 90's the company installed heat pumps and connected the two systems together.

Once it hits 32 degrees, the boiler was supposed to come on. Instead, half the building is cold and the other is hot.

Can anyone please explain what is going on here, and can it be fixed?

In General questions | Asked By Desirae | Nov 23 15
7 Answers

Window advice - Zone 3

Well we are looking at Marvin all Ultrex, Andersen 200, Softlight Elements and Sunrise Vanguard.

We are in Zone 3 on a heavily wooded lot, 4 small window on the west, 2 covered by porch, 15 on the north northwest, 4 on the south and 2 sliding doors, one 6 footer on the south with a 8 ft covered porch and a 12 ft sliding door on the east covered by a 12ft deep screened porch.

What should we look for in U-factor and SHGC?

In Energy efficiency and durability | Asked By Quinton Bryant | Nov 10 15
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