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23 Answers

Lead paint, old clapboards, honoring history

I purchased an 1860 house in Beacon, NY, with 1820 masonry. The aim is to honor the history of the structure while updating the materials where needed with products free of fossil fuels.

Asked By Gregg Zuman | Oct 9 17
7 Answers

Wait to air seal until after blower door test?

I’ve been waiting for cooler weather (in zone 5A) before scheduling an energy audit that includes a blower door test with infrared camera. But now in early fall/late summer is a comfortable time to venture into the attic. Is there any reason to wait until the energy audit to work on obvious air sealing improvements? The only thing that I can really think of is that we might miss out on some potential credits for improvements if our “Before” results limit our improvements.

Asked By andrew c | Sep 13 17
6 Answers

Staple or finish nails to put up tongue and groove wall?

Hi guys,

I bought some 1x6 tongue and groove pine. I will be installing it for my interior walls. I'm leaning towards using a staple gun (1 1/2" staples) to install because its seems like it would be much faster and cheaper.

Are there any downsides I am not thinking of?

Also, should I be face stapling/nailing or will nailing on the tongue be suffecient?

Asked By MichaelBa | Oct 10 17
8 Answers

Radiant barrier, best location

I am planning to install radiant barrier in my attic.

Now, let's get a couple of things out of the way first:
- I live in California; it gets hot here
- I have AC ductwork in the attic. (The duct insulation is 4.2 and I _will_ be replacing it, but that's a separate project.)
- I cannot convert the attic to a conditioned one, as a good part of it is not accessible
- I am also air sealing the attic (well, at least the accessible parts).

I estimate that I am going to need <$200 in material and a weekend of work. Can't go (very) wrong, right?

Asked By brtlmj | Oct 6 17
13 Answers

Is using phase change insulation with ductless minisplits the perfect marriage?

I'm interested in using phase change material with a ductless minisplit heatpump - they seem like the perfect combination. (Also, the phase-change insulation discussion on this site are pushing a decade old and I'm hoping for a refresh.) There seems to be several people selling phase change insulation materials now including - www.insolcorp.com and www.phasechange.com - claiming a 25-35% HVAC reduction.

Asked By Patrick Freeburger | Oct 10 17
8 Answers

What should I use instead of polyethylene?


Asked By Fallwanderer | Oct 9 17
2 Answers

Is my re-roofing strategy adequate?

I just visited the supplier that I'm planning to get my foam board and metal roofing from. I was struggling to decide my strategy before, but now I'm really confused.

I an reroofing a 118 year old bungalow in central Indiana, zone 5. My plan is to tear off shingles to the wood board sheathing, repair, wrap in air barrier/membrane, 2 layers of 2" foam board (probably foil faced polyiso) seams taped and staggered, then horizontal purlins attached with 7"(+) screws.

Asked By Dielectricunion | Oct 11 17
2 Answers

Low-slope roof replacement questions

Thanks for this great resource! I am planning to replace a 30 year-old 3-tab shingled roof on a circa 1959 house with a low slope (~2/12) in zone 2A (Houston, TX). I have been reading through a number of the articles relating to cathedral ceilings and low-sloped roofs, but I still have some questions. More details on the roof:

  • The roof has soffit venting but no ridge vents;
  • The roof system consists of two gable-ended roofs (main house plus garage/utilty room) that meet in a dead valley over about a third of the length of the smaller roof;
Asked By BayouMCM | Oct 10 17
34 Answers

Insulating a low-slope roof

Hi Martin,
We are ready here to go ahead with the insulation of our low-slope roof, and decide to go with closed-cell sprayed foam as you recommended.

We had 3 quotes from local company, and 2 of them proposed to shoot 5-6 inches of foam underneath the 1st deck (in green in the following image), assuming we would remove the interior ceiling.

Asked By Francois Desrochers | Sep 6 17
13 Answers

What would cause water to migrate up through a slab and “sidewalk”?

We have lived in a slab Foundation house for almost two years. When it rains after a dry period we will have enough water come up through slab that it takes a squeegee to get it under control. This happens right at the carport door entry and about a foot away from a half bath wall, as well as into the first six or seven feet of parking area.

Asked By Elaine D | Oct 8 17
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