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11 Answers

Geothermal house air supply

I am trying to re-route my household fresh air intake to run under the ground and enter near the basement floor in order to warm it up in the winter and cool it down in the summer. I live in Wisconsin. I presently bring fresh air into the house constantly and route it to my furnace cold air return. For underground routing, I am concerned about radon gas and water getting into the tubing. I am also concerned about contamination of the air from the tubing.
Thank you,
Dennis Vogt

In Energy efficiency and durability | Asked By Dennis Vogt | Jan 5 13
5 Answers

2x4 wall construction insulation retrofit


I am re-insulating my walls from the inside as this is the only option for me. It seems like any time i do any kind of rehabbing there is a lot on info available but never spot on for my plan.

Structure built 1968
Zone 6, Vermont
2 x 4 wall on slab
Exterior: 1/2" sheeting (no house wrap), 1" board and batten cedar, painted (not stained)

Here is what i have done so far
1. Air sealed with caulk and foam all wood to wood joints, foamed small cavities.
2. Air sealed electrical boxes
3. Installed Roxul r15

The question:

In General questions | Asked By mark kessler | Apr 14 13
6 Answers

Using Roxul in floor joists... dealing with pipes, wires, etc.

Hello, all...

I'm planning on installing Roxul Comfortbatt insulation into the floor joists of my CT home (the floor above an unconditioned basement).

Unfortunately, there are a lot of pipes, wires, conduits, etc. that are within the joists in some areas, and I was wondering if there are any tips on installing Roxul when things are "in the way".

I did search for tips here and elsewhere, but only came up with fiberglass techniques, which seems to be "stuff it in there".

In General questions | Asked By John Reid | Apr 16 13
29 Answers

Mitsubishi rep says minisplit won't work ... back to geo?

So after recommendations on here and other research, I have been in communication with a Mitsubishi rep and a local installer on my new house design. Currently it is roughly 3200 total conditioned square feet (single story with walkout basement). R values are roughly 15,30,40,60, with 7400 HDD in zone 6. Current loads are around 20-22k we think (hope). The plan was to use a single unit with 4 heads. 2 up and 2 down. 1 ducted unit to serve 2 bedrooms and 2 bathrooms, then a wall unit to serve an open living, dining, and kitchen. Similar situation in the basement.

In Mechanicals | Asked By Jesse Lizer | Aug 15 11
1 Answer

Uneven Heating & Cooling on different floors of 2 Story home

Uneven heating or cooling in a multi-level home, situations where the upstairs it's hard to keep cool in the summer or the downstairs is hard to keep warm in the winter - is a very common issue.

In Energy efficiency and durability | Asked By Al Heisner | Apr 15 13
7 Answers

Waterproofing basement from exterior

I need to waterproof my exterior basement wall. Does anyone have any tips, techniques and/or products they recommend? One company mentioned tar, which I think is now illegal to use here in Washington' DC. The wall is made of old bricks which have been parged almost to the footing (long story). The wall sits almost entirely below grade and unfortunately the block and yard slopes towards my house. Any advice is greatly appreciated.


In General questions | Asked By Mary Farrah | Apr 14 13
2 Answers

How well sealed should exterior foam board be?

External Rigid Foam Insulation Board Question: How well sealed should the foam board be?

In Energy efficiency and durability | Asked By Leroy Sloan | Apr 14 13
14 Answers

Is this no-foam, no-stud, no-OSB, no-ply, Passivhaus envelope healthy?

We’re building a small passivhaus in central Vermont. (We’re shooting for PHIUS+ certification.) We’re eschewing the old paradigm of penetrating the outside envelope with HVAC, wiring, plumbing, sockets, switches, etc. (Anything on inside of the the outside wall be just that, on the wall -- i.e., surface-mounted. We don’t like the idea of a service cavity, for several green, labor, material, & space reasons. We will evolutionarily adapt our aesthetic sensibilities.) It will be almost identical to our current house, except we will be using cellulose now where we used foam before.

In PassivHaus | Asked By Greg Whitchurch | Apr 12 13
5 Answers

Surface 4 low-e... condensation issues?

I'm just about to order windows for a project, and leaning towards spec'ing some of the units as double-pane with low-e on surfaces 2 and 4. My sales rep is trying to get current information on exactly which coatings are available, but it appears to be Cardinal 180 on surface 2 and i81 or similar on surface 4. He mentioned that there was uncertainty about the surface 4 coating because there had been some condensation issues when this product line came out.

In General questions | Asked By David Meiland | Apr 10 13
10 Answers

Why won't you answer my questions?

I had just signed up for a free trial. I asked several questions to see the quality of responses. and all I get is access denied.What's up?
How am I supposed to know if you can answer my questions?

In General questions | Asked By margaret kennedy | Apr 12 13
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