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6 Answers

CARB2 Kitchen Cabinets - Formaldehyde

Hi all, Last year we did a kitchen remodel (in California) and my cabinets are CARB2 compliant. I know this because I had some of the plywood independently tested. Post remodel we did an air test (sealed off from the rest of the home) and I'm getting a 150ppb reading for Formaldehyde. I'm dumbfounded by how this happening. Is it possible for CARB compliant cabinets to off gas this much Formaldehyde. Any ideas what else could be driving this? Thanks!

In General questions | Asked By Mike Miller | May 17 15
1 Answer

How to finish basement window

My windows have a frame with recessed sides and top. How do i finish, with drywall or wood?

In Green building techniques | Asked By John Kroeker | May 19 15
3 Answers

We live in an 1895-converted carriage house with an cold damp basement

We live in an 1895-converted carriage house with an cold damp basement made of field stone. We removed mold in the fall and now have the experience of a basement with an average temp of 36 degrees this past winter. SPF was suggested.

We understand EPA is in the midst of looking at long-term outgassing (suggested in a 2011 GBA article), but does not have any answer yet. There was a comment that some chemicals currently used MIGHT be banned in the future....but what facts can a homewowner use to determine whether or not SPF is safe long-term at this time?

In Green products and materials | Asked By Sandra Thomas | May 18 15
2 Answers

The "Perfect Wall" for Conversion Van in Warm/Humid Weather

After thinking about the "Perfect Wall" for an upcoming Van Conversion project, my goal is to use non-toxic, organic and sustainable materials. The base of the van is metal. As for layers I've considered the following starting from metal (inner layer) to floor (outer layer).

1. Lizard Skin Sound Control (Sound/Radiant Barrier)
2. Lizard Ceramic Insulation and/or PermaLoft Wool (Insulation)
3. Recycled Polyethylene (Moisture Barrier)

In Green building techniques | Asked By Sydney Jamila | May 18 15
3 Answers

How apply wallboard to sloping foil-faced polyiso?

In a Green Building Advisor discussion titled "Proper wall to attach rigid foam to the inside of the wall?" on Nov 17, 2014 asking about applying drywall on the interior side installed foil faced polyisocyanurate Martin Holladay responded:

In Green building techniques | Asked By Anthony Vogel | May 19 15
16 Answers

Budget concern: Better to buy the R-10 windows with less-great walls?

A budget crunch forces some tough decisions. Most of the bidders prefer using 2x6s instead of the double stud wall, and using American R-2.5 to 3 windows over the European R-10 ones. My general knowledge is that heat always moves to warm up what is cold, therefore keeping our R-10 windows in the design seems like the place to spend our money. This would mean backing down to an overall R-22 wall (2x6s 24" oc, exterior 1.5" Zip System and another 1" of rigid insulation, well sealed batt or rock wool in the cavity).

In Energy efficiency and durability | Asked By Will Gerstmyer | May 13 15
1 Answer

What are your thoughts about sealing interior poured concrete basement walls and floors?

The basement walls in our newly constructed home are insulated on the outside. We do not plan to finish the basement for a a year or more because we want to watch as everything settles and be able to visually check for cracks. We used a spray-applied water-proofing sealant on the outside of the concrete foundation and Tremco WARM N DRI for exterior insulation and water diversion.

The basement walls and floor were poured in mid-November. Since mid-January we've maintained a temp of 60+ and have kept RH in the 30 - 40% range.

In General questions | Asked By Dave Brooks | May 18 15
2 Answers

What's the most efficient way to run a dehumidifier?

I have tried everything but short of a DER i can't reduce the humidity load of the basement so i have little choice to bring in a dehumidifier.
The one i am getting is oversized according to online sources, 500sqft needs a small dehumidifier but i am getting a 70 pint energy star rated frigidaire (long story). It uses 746W and pulls 70 pints a day at 1.85L/kWh.

In Energy efficiency and durability | Asked By Alan B | May 17 15
1 Answer

Superinsulated Slabs - Vapor Barrier

I'm designing a house for a site in Climate Zone 6B with high groundwater (~36-42" below existing grade during seasonal high water) and in an area of typically high radon. I've been exploring using a FPSF similar to what Alan Gibson described in his April 2010 article on Super-insulated foundations in JLC.


In Green building techniques | Asked By JMS Build | May 18 15
6 Answers

Exterior foam as WRB

I know this question has been asked so many times and I've done my research but can rigid foam be used as a trusted WRB? Specifically XPS? I am in a cold climate and have read in my research that XPS outperforms polyiso. My original plan was 4" of XPS with house wrap over the foam as I will also be installing new windows which will be "outies". I am just confused if the foam is sufficient with the taped joints or if the house wrap is necessary. So much research has been done but there are mixed results and I want to get right on the first try.

In GBA Pro help | Asked By Brian Otten | May 17 15
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