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4 Answers

An acquaintance got an estimate to insulate her 16'x18' crawlspace. Although I haven't seen it personally, here's the scenario:

House is in WI, 7600 degree days, concrete block foundation (no vents to outside) with bare soil in crawlspace. However, the soil is dug down quite a bit deeper next to the foundation, so the soil slopes up towards the center of the crawlspace (about 2.5 ft. high in the middle). Forced air ducts run through the crawlspace, and the access to the crawlspace is a former basement window, which is open to the basement.

In Energy efficiency and durability | Asked By Jonathan Beers | Nov 23 11
5 Answers

We have a home with a sunken living room and we wish to raise the floor approximately 9 inches to make it level with the surrounding rooms. The floor of the sunken living room is slab on grade. On three sides the adjacent floors are over vented crawl space, the fourth side is an exterior wall. To raise the floor I intend to build a frame with a plywood sub floor. With the raised floor should I mimic the surrounding floors, ie create a vented space with insulation up against the plywood sub floor. Or should I create a completely sealed and insulated space with rigid insulation on the slab.

In Energy efficiency and durability | Asked By Molly McCabe | Nov 23 11
9 Answers

Our local historic preservation committee will not allow retrofits/replacement of so called historic windows - the aging, single-pane, wood frame with "wavy" glass. Some in the historic community claim that the existing windows can be retrofitted with films, weatherstripping, insulated shades or the like and match the performance of a high performance (e.g., energy star rated) window replacement.

In Energy efficiency and durability | Asked By mike keesee | Feb 8 11
10 Answers

My house is ICF walls,SIP roof,and 4"EPS under the basement slab. The basement is about 2/3rds the volume of the of the main floor.It is absolutely tight(less than .8ACH) with a vent fan if needed.It is painted a white throughout.It's 9/10ths below grade.Only one door and no windows. The main floor is manufactured "I" beams which are exposed in the basement ceiling.. Measuring air temperature, the basement is always 1degreeC below the main floor.I am told due 97% to irradiation from the white plywood under the 2" concrete slab of the main floor.

In General questions | Asked By Mike Legge | Nov 23 11
1 Answer

I have read of numerous methods for insulation/ vapor barrier.
What is best wall construction? I plan to use, from outside to inside- cypress vertical siding, horizontal furring strips, tyvek, 1/2" plywood, 2x6 studs, spray foam, fiberglass bats, sheetrock/ wood paneling.
House is in Virginia Mountains over basement.

In General questions | Asked By John Waller | Nov 24 11
4 Answers

I've recently begun building energy effecient homes and would like input about how others are attaching rigid foam board to concrete stem walls. I'm using a pier on grade beam foundation which requires 8"-10" of concrete to be covered. I've used all different types of adhesives and haven't found any that stick right away. We usually have to lean a 2x4 against it or shovel some dirt against it.

Any suggestions would be appreciated. We are using Owens Corning 1" foamular 150.

In Green building techniques | Asked By James Fincher | Jul 16 09
4 Answers

This is a question related to the thread on "How to Make a SIP Roof Better". I am building a SIPS house with a nearly flat roof structure- a butterfly roof at 1.25" per foot and a companion roof at 0.5" per foot. The house is in Fredericksburg, VA. Both roofs will have 8" EPS (Neopor) panels. Directly on top of these panels a TPO membrane will be installed.

In Green building techniques | Asked By Ben Raterman | Nov 21 11
20 Answers

Wasn't there a particular dryer vent outlet you were a fan of?

Was it the "Heartland"?

In Green products and materials | Asked By Lucas Durand - 7A | Nov 18 11
5 Answers

On new construction, in Northern NJ, Spray Foam companies are huge advocates of insulating at the rafters. I am an advocate of spray foam, but my experience tells me that unless there is much ductwork in the attic, the attic plane is very complex, or there is a very low ceiling height, I would rather seal and insulate any ductwork properly, and insulate at the attic floor, to keep the overall conditioned space to a minimum.


In Energy efficiency and durability | Asked By Ask Eco Ed Schwartz | Nov 17 11
7 Answers

I am renovating an 8 unit (1 BR) efficiency apartment building in Atlanta GA. The building is block construction, slab on grade, built in the 50s. Even the interior walls are a large brick/block material. The individual units are roughly 500 Sq feet each. I know from talking with contractors and my own mechanical engineering background that I will need a 1 ton central system. Problem is, I can't seem to find a one ton system 13 SEER ir better OR a contractor that can install one.

In Mechanicals | Asked By Jim Clay | Nov 22 11
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