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4 Answers

How much should I be worried of living in a house with spray polyurethane foam insulation surfaces under the floor tiles?

Recently a few surfaces of spray polyurethane foam were installed in
our home, for insulation

In Green products and materials | Asked By Ohad Ben-Cohen | May 15 14
4 Answers

EPS on basement wall -- vapor barrier advisable?

I came across some unfaced 2" EPS for cheap, so I want to use it to insulate my basement walls. I don't know its density but I assume it's whatever is most common. At 4" total, this puts it at about 2-2.5 perms. The perfectionist in me wants to put poly sheet behind it to have a full vapor barrier, but how much difference will that realistically make in the dryness of the basement? It seems like gluing the poly to the wall, and the EPS to the poly would be awkward, and I don't really want to sink anchors into the concrete. I already have a bunch of poly just sitting around.

In Green building techniques | Asked By Nick Welch | May 15 14
5 Answers

Venting a cathedral ceiling with 24" of cellulose

I am building a Passive House with a cathedral ceiling. I used parallel cord trusses with 27" between the top and bottom cords. I will put OSB on the bottom of the trusses as my air barrier and to hold the weight of 24" of loose fill cellulose insulation. I want to vent the roof, but the only baffles I've seen are made of thin vinyl, polystyrene or cardboard. I am afraid that they will be crushed by weight of the cellulose, which would eliminate the air channel. The roof pitch is 10:12 and is 20 feet long, so the baffles at the bottom will be under a lot of pressure.

In PassivHaus | Asked By Gerald Blycker | May 15 14
4 Answers

Would it work to put a solar thermal collector over several GSHP wells to pump hot liquid into the wells all summer?

I would think this method would cause a massive increase in the efficiency of the wells for heating the following winter. You could locate several other wells at a distance to use for cooling in the summer.

In Energy efficiency and durability | Asked By Tom Hanke | May 15 14
2 Answers

We're wanting to install ceramic tile in our bedrooms. Is the orange underlayment necessary, or what exactly is required?

After looking at many installation videos and reading various articles, we are a bit undecided as to what would be the best method.

In Energy efficiency and durability | Asked By Mike Williams | May 16 14
8 Answers

Need consultant expert on residential ERV/HRV air balancing

I live in northern VA suburbs. My residential HVAC system includes a LifeBreath ERV, which has been installed for 5 yrs. During that time, I have had contracts with 3 different HVAC service companies. NONE of them have been able to keep my ERV exhaust & intake air flows balanced.

In GBA Pro help | Asked By Terry Sopher Sr | May 14 14
3 Answers

Why would a builder install propane appliances in a new home?

Did you ever wonder why a new home builder might decide to install a propane furnace? Well, the builder may be getting a $1,500 kickback from a trade group called the "Propane Education & Research Council."

Just to make sure you understand what this program entails, the website explaining the program includes a photo of contractors installing a huge underground propane tank.


In General questions | Asked By Martin Holladay | May 15 14
7 Answers

Efficiency per inch for 2-lb. closed-cell spray foam

With most things with layers, each layer provides a different level of efficiency which you can then take this and apply cost to find your best number of layers to go. Does anyone know how many inches of 2# closed cell spray foam is the optimum? I talked to one contractor that said that the first 2" of the foam provide 90% efficiency. Does this sound right? Or should you be looking at going 4" or more? How does one determine how much is enough and the rest is overkill?


In Energy efficiency and durability | Asked By Greg Thornton | May 13 14
5 Answers

Green getting greedy ...

In General questions | Asked By flitch plate | May 14 14
2 Answers

Please recommend an affordable deck cable railing system?

I am trying to select an affordable, sturdy, deck cable railing system to preserve the maximum view for my lakefront home. I have ruled out a glass railing system. Would appreciate any suggestions of manufacturers of kits. Thank You.

Joe, Connecticut

In General questions | Asked By JOSEPH POLAND | May 15 14
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