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4 Answers

Radon venting in 1/2" crushed rock?

I have about 9" of 1/2" crushed stone as a base for the slab (2" of foam will go between stone and slab). I searched for clean, no fines, and the best I was able to get is mediocre clean.

Will installing 4" perforated PVC pipe in this material still work as a radon vent?

Would the efficacy be improved if I backfilled the 8" deep x 8" wide trench for the pipe with 3/4" rock?

How long should the pipe be?

Thanks.

Asked By David McNeely | Feb 9 16
2 Answers

Spray foam directly on underside of roof?

I have a conditioned attic, currently insulated with R19 fiberbatts between the rafters. No airsealing, hence I want to remove the fiberbatts and spray 3 inches of closed cell spray foam in before putting the fiberbatts back in place. The attic is unvented, for instance no ridge vent exists. Should I put any membrane or the like on the underside of the roof sheathing before spraying the foam in ? I was thinking that would help with keeping the insulation intact in case the roof needed repair later on?

Asked By matthias paustian | Feb 9 16
1 Answer

Does a rainscreen assembly maintain the exterior surface of paint?

I am trying to argue for a rain screen assembly. Is there any evidence that would highlight extending the time between painting the exterior siding by using a rain screen?

Asked By Julie Klump | Feb 9 16
7 Answers

Using a second water heater as an indirect fired tank?

I have two water heaters. A 50 gallon HTP Phoenix Light Duty propane water heater, and a 50 gallon electric resistance water heater. The two heaters are plumbed in series, electric water heater first, then propane. To make a long story short, some things didn't work out as originally planned, and now I'm paying an extra $15-20/month (and wasting source energy) because I'm heating up a bunch of water with electric resistance right next to a high efficiency propane water heater.

I'd like to stop doing that. I have a couple of extra constraints:

Asked By Tim C | Feb 8 16
8 Answers

Tiny house building -- mold and off-gassing prevention

Hi, I am going to be building a tiny house DIY. I have not built walls myself, but have done most everything else in a house I had owned, taking it down to the studs to rebuild. One of the reasons I am building a tiny house is that I have extreme health needs. Because of lung disease and a mast cell disorder, I react to small amounts of mold, environmental pollutants (formaldehyde, cigarette smoke), foods, etc. Since these issues have become graver, I have lived in just one place I would consider relatively safe, my current home.

Asked By Emmy Haus | Feb 8 16
29 Answers

Best insulation for indoor air quality?

I cannot decide on a type of insulation for our new home. I want something that is the safest for indoor air quality. I am worried about the off gassing of spray foam, but am also worried about the borate used in blown in cellulose (mainly the reproductive effects of borate). Please help! I want energy efficiency, but indoor air quality is of primary concern. Thank you!

Asked By Carolyn Farrow | Feb 8 16
4 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.

Asked By Zach H | Feb 3 16
7 Answers

Air exchange / ventilation / dehumidifier options for a sealed, 640 s.f. structure

I am building a 640 s.f. structure and insulating i twith closed cell spray foam. Heat is provided by a fireplace with an outside air supply and baseboard heat.

I need an energy-efficient air conditioning / ventilation / dehmidifier / air exchange solution, mainly to keep it dry, but also to keep it cool.

It is located in a typical, four season climate where we get hot, humid summers and cold, snowy winters.

Asked By Nathan Hiscock | Feb 8 16
2 Answers

What happens when Tyvek goes uncovered too long?

I am a resident in a new apartment building in SC. I read the article on Tyvek and have reviewed that Tyvek has between 4-9 months to go uncovered before it expires. It has been 6 months, and the outside of our building is for the most part finished but has large areas of uncovered Tyvek. Recently my roommate and I noticed that at the bottom of our large windows we found large sums of puddled condensation and mold growing. Is this a result of the Tyvek being uncovered? We are not the only residents to have found this problem.

Asked By lindsey adams | Feb 9 16
5 Answers

Infrared panel heat: any reviews?

I am heating my zone 6 2300sf house with minisplits and a propane fireplace. The bathrooms, however are more isolated in the floor plan. I had been considering supplemental infloor electric radiant or kickspace heaters until I discovered ceiling- or wall-mounted infrared heating panels. The smallest 250w glass or steel units look like they easily heat 50sf rooms. Some are even available as a mirror. It looks like an efficient way to occasionally heat rooms that have air pulled into the HRV. Are there any good independent reviews out there on the concept?

Asked By Edward Mallett | Feb 8 16
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