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0 Answers

Wall assembly

I am building a new home in zone 6. I have a question regarding insulation in the window wells. I have 4 inches of xps externally. Of course I do not have insulation inside the window well area. That leaves the header area and a small amount around the window uninsulated. Should I use an internal insulation in the stud bays around this area? One window well is in a bathroom. Should a smart membrane be installed in this area?

In General questions | Asked By Charles Cloud | Feb 4 16
0 Answers

What is best & permanent adhesive and sealant for metal roof screws/seams?

I have a u-channel metal roof. The washer screws that go through the roof into the plywood and rafters are backing out dozens a year and many are stripped. I want to tighten or replace them as needed and use something to keep them in as well as seal the threads and gaps watertight.

Any suggestions on procedures and materials?

Also, what is the proper location to put the screws? Through the raised part or the valleys? I see both on my roof.

In Energy efficiency and durability | Asked By Andy Nels | Feb 3 16
30 Answers

How to reduce radon level in my house?

When I first bought my house a couple of years ago the radon test was conducted in the first floor (bi-level house on concrete slab, all above grade) showed 3.5. A couple of years have now passed and I have since replaced all the windows and sealed all the gaps I could possibly find. Last week I did the same test again (using the same setup as my home inspector) and it was 12.1, ouch! Does it mean I made the first level too tight? What are my options to fix it?

In General questions | Asked By Joe Blanco | Jan 22 16
0 Answers

Chinese Split Heat Pump Water Heaters

Sanden is getting a lot of attention due to their Eco-Cute split heat pump water heater using CO2 refrigerant.

In China though there seem to be many manufacturers making split heat pump water heaters using Japanese compressors (albeit with more common refrigerants). On alibaba.com or made-in-china.com do a search for "heat pump water heater" or "evi heat pump" or "twin rotary heat pump" and the options seem to be endless.

In Mechanicals | Asked By Osman Anwer | Feb 3 16
0 Answers

Alternatives to SPF to insulate floor

I have a late 50's ranch house with a vented crawlspace in the San Francisco bay area. There are remnants of old cellulose insulation in the vented attic, though very little remains. The rest of the house is pretty much uninsulated. Even though we are in N. California, the weather gets chilly, and predictably my hardwood floors (and stone/tile floors in the kitchen and baths) have been very cold this winter. I am in the process of finding a good contractor to do a whole home energy audit, and come up with solutions (as green as possible) to make the house more comfortable (i.e.

In General questions | Asked By Zach H | Feb 3 16
0 Answers

Basement Remodel/Subfloor questions

I have a few questions about my plan to insulate a subfloor in the basement.

Let me provided the pertinent details and my purposed plan.

The brick ranch house located in zone 4a (Virginia) was built in 1965. It has both an above and below grade basement. The structure is concrete block. The front long wall and one short wall are completely below grade. The back wall and half of the other side wall are above grade. The basement is conditioned.

In Energy efficiency and durability | Asked By Steve Basic | Feb 3 16
0 Answers

Thermoarcilla? Termoarcilla? Thermal Clay?

I've been working with a Spanish carpenter who told me that a lot of walls in Spain are being built with Thermal Clay, which I guess is the translation of Termoarcilla. I have had greast difficulty fining much information online in English (sorry my Spanish is not so good).

Here is some information: http://bloquetermoarcilla.es/en/productos-termoarcilla.php

In Green products and materials | Asked By E T | Feb 3 16
8 Answers

Roxul comfort board in basement?

I spoke to someone at the Roxul company the other day who recommended the following basement insulation. First, tyvek or similar against the concrete basement wall, then 1 1/4 " roxul comfort board for a thermal break, then a stud wall filled with roxul batts--- sheetrock. Do you see a real problem with water condensing on the concrete with the comfort board and tyvek there? Still seems like too much work but I am curious performance wise.

In Energy efficiency and durability | Asked By Nyle Phillips | Sep 27 12
31 Answers

Which Weather Resistive Barrier behind new masonry?

I'm coming up on a project involving cladding Structural Insulated Panels (SIPs) with a full-thickness veneer natural stone wall. So, from the outside in, it will be stone - 1" gap - WRB - 6.5" SIP panel.

Question: Which WRB is preferable?
Context: I am in northwest Ohio.

The following page on this site's Product Guide lists a number of products, but links only to manufacturers' info: http://www.greenbuildingadvisor.com/product-guide/cat/water-resistive-ba...

In Green products and materials | Asked By Andy Chappell-Dick | Jun 11 13
0 Answers

Moisture accumulating before vapor barrier installed.

I'm in zone 7A and built an attached garage this fall: in slab heat, 2X6 walls, Rex wrap and OSB sheeting. The in floor heat got hooked up and turned on the beginning of January at the same time I began insulating the walls with unfaced fiberglass batts and faced batts in the ceiling.

Before I got poly vapor barrier up on the inside, there was a large amount of moisture (it was frost when it was cold outside) accumulating on the inside of the sheeting behind the batts.

In General questions | Asked By Neil Knutson | Feb 3 16
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