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1 Answer

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
21 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
26 Answers

Best way to fix insulation problem in cathedral ceiling? Please help!

I built my chalet about 8 yrs ago and was up in the attic and noticed black water stains (probably mold).
after many days and night researching what was wrong, i believe my issue is insulation and air leakage.
i have called all the insulation and roofing businesses (not many in this area) and each says its the others issue.

this site has been the most informative, but i cant seem to find any article or videos on how to add or change insulation in a cathedral ceiling after construction has been done.

Asked By Aaron H | Jan 31 16
2 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
3 Answers

I have a crawl space with cold joints that are inadequately sealed and ooze water. How can I seal them?

I would like to do it healthfully and effectively so I don't have to be concerned about water intrusion in the future.

Asked By Kevin Krafft | Feb 7 16
5 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
1 Answer

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
3 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
1 Answer

Perlite vs. rigid foam insulation

Hello have a question that will probably generate many opinions, i am building a new house zone 5 , was planing on using rigid foam under slab , but some one recommended that i use Perlite in bags instead , says
1) easier to work with
2) easier to pour slab over as you can level things out with sand
3) cost about the same or cheaper then ridged Foam
4) has better R value

Asked By Boris Rubinstein | Feb 8 16
7 Answers

Will this exterior wall system work for my tiny house?

I live in South Dakota in zone 6a (Sioux Falls). In a few months time I will be constructing a tiny house on wheels using 18 gauge structural studs. Starting in the wall cavity will be sprayed closed cell foam. On the exterior sides of the studs (and any other exposed metal areas- the steel trailer) I plan on using strips of 1 inch thick xps rigid foam with a compressive strength of 60 lbs/square inch. Also I will use steel strapping all around the outside to give it some shear strength and prevent racking.

Asked By Damon Beck | Feb 7 16
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