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2 Answers

I plan on finishing off the basement of a 1970s house. This house has poured concrete walls with 1" XPS foam board on the outside of the basement wall (down to the footings) with foam also on the rim joist. Will installing 2" XPS on the inside wall and rim joist cause problems?

In Energy efficiency and durability | Asked By Dan Janssen | Jun 4 10
2 Answers

Besides the basement being musty my upstairs rooms in my 4 story brownstone also have that musty smell. I believe the basement air is being drawn up (stack effect) in the both the old non-working fireplaces ( 2 per floor) and in the annular space between the exterior brick and plaster walls. Should I also blow in insulation in this annular space and seal the fireplaces?

In General questions | Asked By Chris Haun | Jun 3 10
2 Answers

The New EPA rules require the use and disposal of 6 mil plastic in all lead safe projects. The simple preparation of an average sized bedroom could use a minimum of 12 yards of plastic, the paint and prep of a 2000 square foot single family ranch could use well over 200 yards of plastic on the floors alone, plastic will also be required for doorways, windows, immovable furniture, if the exterior is also painted add an additional 300 yards. 500 yards of plastic not including plastic covering, doors, windows and vents.

In General questions | Asked By Sam | Jun 2 10
7 Answers

I'm going to be building a single familyhome soon, and I have been researching passive solar, trombe walls and heat sinks. My home will have a sourthern exposure with significant glass on this facing wall. I'm looking for information on the advantages and disadvantages on trombe walls with very little success, but I have really found very little on heat sinks. I'm wondering if there is a material that would act as a heat sink yet at the same time not be too heavy which would require structural modifications as I plan on having a full basement under this possible heat sink.

In Green building techniques | Asked By John Sensenstein | May 17 10
3 Answers

Hi all,

We need to make a decision about chimney cap design, soon. In the region there seem to be two main designs. More than the looks I wonder about the efficiency:
1) a simple triangular finish, with two flat pieces of terracotta making a triangle (as if you had put two playing cards to make a tent), that sits on the square base of the chimney that sits on the roof.

2) or a square/rectangular base which finishes with single bricks standing on their narrow ends on each corner of this with a flat piece of stone on top (like a little table that sits on the chimney).

In Energy efficiency and durability | Asked By Canan | Jun 1 10
5 Answers

I have heard rave reviews about the Rinnai Tankless hot water heater. I would like to know if it is better than other options that may be given a more general name of "solar hot water heater". I believe the solar hot water heaters are much more expensive. Please clearly define some specific name brands and general prices of solar hot water heaters.

In Green products and materials | Asked By Melissa Rives | May 28 09
3 Answers

I recently purchased a vacant lot in Charlotte, NC that has good southern exposure. I am researching architects and builders that have experience with passive solar homes. I'm not finding many local people with a portfolio of existing jobs. My wife and I want to look at the professional's previous work to help us determine competence in passive solar techniques and to help determine whether our aesthetic visions are compatible. Ideally, I think it would be best for logistics and communications to find a local expert. Can anyone recommend some Charlotte-based people?

In Project management | Asked By Brett Moyer | Dec 23 09
3 Answers

1988 1.5 story home with heat pump/electric backup

Project: Affordable Green Upgrade to Net Zero Energy

Specs today:

2000 sq. ft., standard 2x6, fiberglass batt, OSB sheathing, no tape, no building wrap, no rim-joist insulation, and vented roof leaking warm inside air. 40 million BTU annual heat load.
R-5 true whole-wall R (R-19 glass batts perform poorly in leaky wall at low outside temps)
R-15 attic/roof (R-38 glass batts with venting leaking heated air out)
R-1 cellar (R-11 batts 1" off wall, short of floor by 1')
R-.5 rim joist (no insulation, no caulking)

In Green building techniques | Asked By adkjac upstateny | Jun 1 10
3 Answers

Hi again. You may recall that I live in Baltimore, Maryland, and am planning an addition to my home. I live in a brick masonry 2 wythe load bearing house built in 1938. I see this also as an opportunity to retrofit my house, that would keep the house as an integrated system. In have been thinking about doing a "chainsaw retrofit"/PERSIST, except there is no chainsaw because my existing roof has no overhang or soffit, with only gable end window ventilation.

In Green building techniques | Asked By Richard Ugarte | May 30 10
1 Answer

Are air admittance valves on plumbing vent stacks an acceptable method of reducing roof penetrations in an attempt to minimize energy loss?

In Energy efficiency and durability | Asked By NelsonL | Jun 1 10
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