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4 Answers

Spray foam - how thick to air seal a rim joist?

What is the minimum thickness of spray foam on a rim joist for effective air sealing? I'm using a disposable 2 part 200 board foot kit.

Asked By Walter Gayeski | Sep 4 14
8 Answers

Tamarack Cape vent dampers

Hello all - I'm a bit intrigued by Tamarack cape dampers - I've searched here and found a couple of threads that include some mention of these units, as possible solutions to issues in specific applications (wood stove OAK, and HVAC duct). I wonder if anyone has any experience with this style of damper in a bath fan exhaust? Apparently they've been around for @ 5 years. Rated to 160 deg F but I have no idea how they would perform under extreme cold conditions (such as what this winter has brought us). Any insights or comments are greatly appreciated. Thanks....

Asked By Randy Toni | Mar 26 14
6 Answers

Used XPS or new EPS for outer layer of over roof insulation

I can get reclaimed 3" XPS and 4" ISO insulation locally for less than half the cost of new material. I am planning to reroof and put 4" of ISO over the roof deck then a second layer of foam above that. I am in zone 5B and need at least R-20 above the deck to control the dewpoint (quick thank you to Martin for providing a place and tools to learn about these things).

Although XPS has a high GWP this is used so should I care, or should I get new nailbase with EPS?

Thanks
Eric

Asked By Eric West | Sep 5 14
4 Answers

Do fans help to dry objects when dehumidifier is running?

Project is a nonprofit archives building in Maharastra State, India. It has a double wall of thick masonry to provide a thermos effect that is effective at evening both annual and diurnal temperature fluctuation. The inner room (that holds the artifacts) has no opening but a door and egress, and is very airtight. No human needs, so no mechanical ventilation.

Humidity control remains an issue. Currently a small portable is proving almost adequate. Heating and cooling is not necessary.

Asked By David McNeely | Sep 6 14
3 Answers

Open-cell spray foam vs. Roxul

Again I am asking insulation questions. I have a bid for a full foam compliment in my new construction home. They want to do 4" of open cell in the exterior walls trouble is my walls are 2x6 and it just doesn't make sense to leave that area open to me plus the foam performs best at 4" thick so I understand the cost difference for payback on no the extra inch is tough to justify.

R-14 in the stud bays with the r-9 outside with polyiso just seems a little short on r value to me??? Seems like I can do better.

Asked By Anthony Hughes | Sep 4 14
8 Answers

Ventless heat pump clothes dryer

Would a ventless heat pump dryer contribute to indoor humidity and heat levels?

I thought the unit was all self-contained and would NOT contribute to increasing moisture and heat in the room it was located in. If anything, it would only dispense water from the drain line into a sink drain but that's about it. Am I wrong?

Asked By Peter L | Sep 5 14
8 Answers

Humidity being trapped between an inside vapor barrier and OSB?

As a potential solution for concern about OSB being a vapor barrier, and all the related potential problems for humidity being trapped between the inside vapor barrier and the OSB, an architect has recommended to me to drill 1/2-inch holes every 8 inches throughout the OSB panels to allow humidity to escape to the outside, while the housewrap will prevent water from entering into the OSB.

I would like you to comment on the value of this recommendation.

Thank you in advance for your help,
Regards

Pierre Gingras
Canada

Asked By Pierre Gingras | Sep 7 14
44 Answers

Dare to DIY a mini split install?

Hi all,
Can editors step out from behind the curtain to ask opinions, too? I'm planning to redo my garage shop this Fall and although my primary heat for the space is a woodstove, I'd love to have some supplemental heating, and cooling in the summer would be great, too. I'm no schlep when it comes to remodeling work, but have never installed or seen a mini split install. Would I be a fool to try the install myself or have the kits gotten streamlined to the point that its basically plug and play, complete with factory-charged units and quick connect line sets, etc?

Asked By Justin Fink | Aug 22 13
44 Answers

Installed R-60 insulation in attic... now using AC more than before

I had R60 blown into my 1000sqft attic where there was previously only about R11. Baffles were installed in almost every roof rafter. Air sealing of attic floor was performed. This is a low pitch asphalt shingled hip roof over the whole house.

Asked By Jeff Watson | Jul 12 14
2 Answers

Masonry cement odor

We installed a Boral synthetic stone surround using Tolteca type s masonry cement at an interior wall fireplace renovation. After 6 months there is still an odor coming from the surround. That wet mud, almost gym sock smell that varies in intensity with weather changes. Boral says it cannot be the stone and the mason says he has no history or reports of this odor. We have had environmental testing for VOC, MVOC, swab, and mold. No issues, but smell was corroborated by them.
What can we do except rip it out?

Asked By John Bertelsen | Sep 6 14
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