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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
3 Answers

Choosing insulation.

I'm still trying to decide a few details of my walls. If i choose dense packed cellulose what r/ " should I expect.? In searching this topic I've found values ranging from 3'0/" to 4.0/" Is there an agreed value supported by actual testing? If I should choose Roxul comfort bat I know the maximum r value but must degrade that to account for installation imperfections. Does anyone have any insight on how to estimate the degradation in a double stud wall with 3 layers of bat insulation?

In Energy efficiency and durability | Asked By Jerry Liebler | Apr 12 13
20 Answers

AAC or conventional "green" -- which way to go?

My wife and I want to build a healthy house. We both have chemical sensitives that make "usual" building practices undesirable. Before the market bottomed, we were planning to build a healthy house following BauBiology practices (as much as practical) and using autoclaved aerated concrete for the structure.

In Green building techniques | Asked By Steven Knapp | Mar 31 13
5 Answers

Properly balanced ventilation system

Concerning a one year old home with all above grade walls and roof sheathing insulated with open cell spray foam and basement interior foundation insulated with closed cell spray foam insulation. Two ERV's with the exhaust from the bathrooms and the fresh air supply connected to the air handles return. With the air ERV's and handler fan on the house is under a negative 5.5 pascal pressure measured on the first floor with respect to the outside.

In Mechanicals | Asked By Flemming Lund | Apr 12 13
8 Answers

Device to charge electric vehicle battery from PV during grid outage and draw from EV battery at night?

Has anyone heard of a manufacturer developing a device that would allow a homeowner to charge their electric vehicle battery from their PV array during the day and draw from EV battery at night during a grid outage, basically using the vehicle battery as one would on a off grid PV/battery-array system?

In Green products and materials | Asked By Marie McMahon | Apr 10 13
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