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1 Answer

Hydronic tubing above or below subfloor?

I'm getting ready to do renovate my 1956 cape cod in Delaware. The house is heated with hot-water baseboard radiators throughout (supplied by a 120,000 BTU gas-fired boiler at 180F). In the remodeled kitchen, I'll be putting cabinets where the existing radiators are. Floor will be ceramic tile rather than the current vinyl sheet, over 3/4" plywood.

While I could install toe-kick radiators under the cabinets, I'd prefer in-floor hydronic heating throughout the kitchen. I've had it in a couple of prior houses, and liked it a lot.

Asked By Tim in Delaware | Apr 24 17
4 Answers

Hip roof in Zone 6A

My client is a builder who has already completed the exterior siding and roofing of a new house in coastal Maine (zone 6A). The hipped roof and 2x6 walls have no exterior rigid insulation and no air space between cedar shingles and Typar. Walls: 2x6 with R-21 batt (John Mansfield), 1/2" CDX, Typar, cedar shingles. He plans to install shiplap hemlock paneling to the interior. Roof: Hip, 6 in 12 pitch, 2x10 rafters into (2) 11 7/8" hip rafters. Also has two dormers.

Assuming we go with an unvented assembly, how do we best achieve a vapor seal?

Asked By user-6825743 | Apr 22 17
7 Answers

Raycore - is it the product for me?

I was pretty much on board with buying Raycore for the 4500 s.f. home I am building in downstate NY, which is steel framed, so I actually don't need any structural value out of the exterior walls other than for supporting the windows and doors (and supporting the walls themselves). I am also going with a wire lathe and stucco on the exterior - Raycore told me I could direct apply the wire lathe and did not have to use any sheathing if I did not need the shear strength, but I am hesitant to do so.

Asked By Joe McCarthy | Jul 14 14
5 Answers

Stone wool versus blown-in cellulose insulation in double wall assembly

I am designing a wall assembly for a home in a very cold climate Zone 7. Considering labor and material costs, what is the most cost effective insulation providing me with the highest thermal resistance? I like the fire resistance of Roxul stone wool batts and the idea that it's more DIY. How about the air transference between the two products? Thanks.

Asked By Matthew Michaud | Dec 30 12
6 Answers

March for Science

I'm sure that many GBA readers spent yesterday at their local March for Science protest. My wife and I, along with several friends, joined researchers, academics, middle-school science teachers, and lots ordinary people who care about the planet (and who use accepted means of separating truth from falsehood) at one of the hundreds of marches that happened all over the world yesterday.

Lots of good signs. Among my favorites: "I can't believe I'm marching for facts" and "Knowing Stuff is Good -- Seriously, why do I even have to march for this?"

Asked By Martin Holladay | Apr 23 17
0 Answers

crawl space mold

1st off, where are my manners, thank you Martin for your answer regarding using damaged 4" roof mate for foundation walls. i did ask my building inspector about it as well...i was thrilled that he said yes and i didn't need to apply a fire-barrier like drywall to it. my guess is, because it's only 2' high and there is absolutely no storage in it.

Asked By nepal | Apr 24 17
4 Answers

Can straw bales be used on the exterior of a shipping container home?

I am interested in building a shipping container home. Insulation is one of my biggest concerns. I have read a lot about the benefits of straw bales. I am very interested in using this as the exterior insulation, but have not found any info pro or con. Any help will be very beneficial.
Thanks for your info.

Asked By OrrinH | Apr 23 17
8 Answers

Roof membrane in ceiling?

In a commercial application we are putting a new floor over an existing roof that has an EPDM or TPO roof membrane on it. We feel this membrane should be removed for a variety of reasons, but, are getting questions from builders if it's necessary. If left, it would above a dropped ceiling, below the new floor deck. Is there a code addressing this or literature backing up it's removal? Thank you.

Asked By BryanD14 | Apr 24 17
1 Answer

I need some insulation


I am thinking about adding insulation in our NY beach house. The house is an “upside down” house that has exposed “tongue and groove” vaulted ceiling upstairs. We like the look of the ceiling with rafters and boards exposed but are not sure how to add insulation to the roof to enjoy winter. On the exterior roof we currently just have a water barrier with two layers of asphalt shingles. So there is no insulation. We have a forced air heating system but it’s incredibly inefficient considering our level of insulation.

Asked By beachhouse123 | Apr 24 17
2 Answers

Deep blown in cellulose for attic - questions

I have a few questions regarding deep (beyond R60) blown in cellulose for an attic. Cellulose is relatively cheap and I'd like to maximise my attic insulation without causing any other issues:

1. Several manufacturers of cellulose insulation have depth/R-value charts that stop at R60. Is there any practical reason for this, or is it just because most people don't bother going above R60?

2. Does compression above a certain depth negatively affect the performance of the insulation in any way? I.E. does your R-value/$ go down appreciably beyond a certain depth?

Asked By Lance Peters | Apr 24 17
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