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10 Answers

Effective and affordable way to air seal between sill plate and slab

Hi. I am trying to find out more information on ways to effectively air seal the pressure treated sill onto a concrete slab? I have run across foam sill sealers, such as Pactiv Green Guard and have also read about acoustic sealant caulking. Of course, conflicting opinions exist.
Has there been any study on the longevity and effectiveness of these materials? For example, I can picture over a decade, that the acoustic sealant would become brittle and cracked, letting air infiltrate.

Any information would be appreciated. Thanks in advance.


In Green products and materials | Asked By Matthew Michaud | Nov 25 13
2 Answers

Insulation under brick veneer installed over steel framing

What is the best way to insulate a steel framed wall which will be brick veneered?

In Green building techniques | Asked By Raymond Hughey | Nov 27 13
3 Answers

What should I look out for with metal roofing installations?

I understand the up-sides of metal roofing - standing seam, corrugated, B-deck type profiles. What are the down-sides

In General questions | Asked By Daniel Clapp | Nov 27 13
9 Answers

Can I put a ductless mini split condensor/compressor in an unconditioned cellar?

We are renovating a 125 year old masonry building in NYC. We are heating and cooling it with ductless mini splits. They run more efficiently in a warmer environment (in winter) and cooler environment (in summer). So why not install them in the cellar which should stay about 50 degrees all year. Any thoughts on this? Possible hazards? Thanks Daniel

In Mechanicals | Asked By Daniel Herskowitz | Nov 22 13
6 Answers

Why vent in an unvented roof design for snow region?

In Joseph Lstiburek's book ' Builder's Guide TO Cold Climates ' ,in discussing unvented roof designs, he says " In extreme snow regions it is necessary to add a vented air space between the roof cladding (shingles) and the rigid insulation to flush heat trapped due to insulating value of the snow..."
Why does this heating of the cladding require venting ? condensation ? ice dams ?

In Green building techniques | Asked By Brian de Gruchy | Nov 25 13
1 Answer

Are whole-house fans worth the trade-off in missing insulation?

Are whole house fans worth the trade off in missing insulation? i like using them. my builder says we will be missing a lot of insulation because of it.

In Energy efficiency and durability | Asked By lisa lockwood | Nov 26 13
2 Answers

Adhering/fastening mineral wool to walls

Quick question. building a new house.. now at "wrap house with Zip sheathing -- taped seams" stage. Zone 4c/5 border near Long Island Sound shore.

Soon, we'll likely cover with 4" of mineral wool. Ostensibly fastened/tied down with 2x4 furring screwed through the m.wool. then, fiber cement attached to the 2x4.

A. Thoughts on squash block requirements between the studs (to prevent the fiber cement from bowing and or breaking because of the unsupported void which is required for rain/drain plane. and or to prevent gradual wind blown pressure on the siding...

In Green building techniques | Asked By pat rowland | Nov 26 13
7 Answers

So let me make sure I am understanding this site. You sign up and get access to nothing unless you get a GBA Pro account.

So let me make sure I am understanding this site. You sign up for site and get access to nothing unless you get a GBA Pro account. Is that correct?

In General questions | Asked By chuck breslin | Nov 26 13
2 Answers

Indoor humidity

I have a moisture problem in my house. My windows, which are all new, freeze shut when it gets to be about 20 degrees. I suspect the basement slab is where the moisture is coming from. There are no leaks in the roof or walls, and the windows are properly flashed and insulated. I have removed a section of slab for plumbing purposes in the past, and it was really wet underneath with no poly or insulation. My neighbor has a house of the same era with the same problem. I don't have actual water coming into my basement, but I don't know where else the moisture would be coming from.

In Green building techniques | Asked By ben grzadzielewski | Nov 26 13
2 Answers

Should I use XPS or ISO on my house?

We are planning on covering our house with one inch of rigid foam in connection with a gut renovation. The house is located in Zone 5A and is constructed with 2x4 walls that will be dense packed with cellulose.

One inch of XPS or ISO will suffice from "dew point" perspective to keep the dew point out of the wall cavity. My concern is that the ISO could potentially take on water resulting in a r-value of less than 5 and that based on my research it would have an effective r-value of less than 5 in situations in which it is very cold outside.

In Green products and materials | Asked By Orrin Levine | Nov 26 13
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