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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
2 Answers

Polyethylene quality and characteristics

Hi. I have come across various qualities of polyethylene for use under my slab. The prices vary considerably; from ~$120 to $280 for 10 mil 20'x100'. I have been told that thickness being equal, some brands will degrade in a very short period of time (matter of years), as well as off-gas significantly more. They claim that the type that is "agricultural/construction film" are cheap and not intended for under slab use. Is there truth to this, and should I shell out 65-75% more money for the "better" grade plastic? Thanks in advance.

In General questions | Asked By Matthew Michaud | May 14 14
2 Answers

ERV for a basement apartment

We are renovating a 900 sq. foot basement apartment in Beacon, NY (Hudson Valley - area code 12508). It's partly below grade, and pretty tight with new double pane windows.

We're thinking of putting in an ERV for ventilation since:
1) We think that having the availability of ventilation in the basement apartment is a good thing.
2) We've noticed a slight mustiness in there.

In GBA Pro help | Asked By Yaakov Weintraub | May 15 14
1 Answer

Advantech exterior sheathing permeability and wall drying

Hi. I am worried that my plan to use Advantech 1/2" (WRB over it) as my exterior sheathing will not allow my wall to dry to the outside. I have heard that the perm rating of this product is 2-3. Is there way to install the sheathing with very small gaps to improve the chance of moisture to escape? Should I even be worried about it? Thanks.

In General questions | Asked By Matthew Michaud | May 14 14
5 Answers

Should I insulate one of my exterior foundation walls?

I am getting some water penetration through a block wall in my basement and through the floor near the bottom of the same wall. The ground on that side of my house is currently sloping towards the house and inviting water inside. I was thinking of excavating that side of the foundation and applying a waterproof membrane to the exterior and then regrading the ground to make it slope away from the house.

In Energy efficiency and durability | Asked By Kevin Schramm | May 12 14
5 Answers

Wood fence post foundation in Wisconsin

I'm interested in wood fence durability in cold climates. I am planning on installing a 5ft picket fence using 10ft cedar 4x4 posts this weekend. The posts will be buried 5ft deep and spaced 5ft apart. Will be using a skid steer with a 10" auger to make short order of holes. I want to stay away from setting posts with concrete or foam because I may be moving the fence in a couple of years (and want to minimize materials I am using). I live in Madison, WI where the frost line should be 3-4 ft.

My questions are:

In Energy efficiency and durability | Asked By Kristopher Steege-Reimann | May 6 14
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