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8 Answers
Necessity for rainscreen approach w/ 5700 HDD & Hardiepanel

I'm curious about rainscreens, which seem to be reccomended by building science experts, but not reccomended by manufacturers. A case in point: James Hardie Inc does not reccomend a rainscreen behind its Hardiepanel product, but there seems to be some kind of loose consensus that you will have water and mold problems unless you use a rainscreen behind a product like Hardiepanel.

Asked By Michael Chelnov | Feb 26 10
1 Answer
Where can I find engineers who have practiced spacing timber studs greater than 24inches on-center?

I have developed a program to calculate maximum on-centers relative to combined compressive and bending loads for timber used as studs. The goal is, for example, to use less material to construct a home. Where could I find an engineer, architect or contractor who has worked on such a project, their experience and results? Many thanks!

Asked By Peyton | Mar 11 10
3 Answers
Combined permabilty of 1" unfaced (expanded) EPS and 3/4" extruded?

I am residing a 30 year old house in North Jersey. In order to match the exisiting house I need to add about 1 and 3/4 inch filler over the 1/2 plywood sheathing to some exterior walls before reinstalling vinyl siding.

Over the 1/2 plywood, I have been using using 1 inch unfaced expanded poly (i remove the plastic backer as I dont know if that is permiable) then use 3/4 extruded poly (I punch about 100 nail holes first to ensure it breaths)

THere is no vapor barrier inside other than standard r 11 fraft faced insulation

So my questions are,

Asked By Ken Gilbert | Mar 10 10
4 Answers
New video

We've posted a new video -- an interview with Al Rossetto -- here:
http://www.greenbuildingadvisor.com/blogs/dept/green-building-news/do-it...

In the video, Al discusses walls without thermal bridging, dry foundations, ERV ventilation systems, and radon.

Asked By Martin Holladay | Mar 9 10
6 Answers
How much room heat do Heat Pump Water Heaters need?

These seem like a great idea if one needs to heat water with electricity but will a heat pump water heater be effective if enclosed in a small, unheated mechanical room in a basement kept at a low room temperature? This is in a heating climate and we don't need air conditioning. My logic (and it may be faulty) tells me that, eventually, the room would cool to a point where the heat pump would quit working efficiently.

Asked By Donald Lintner | Mar 8 10
12 Answers
Walls, Moisture .... and Paint.

For a Pacific Northwest house, we're recommending R-30 in the walls, and proposing to achieve it with: (Metal and/or wood siding) 1-1/4" Extruded Polystyrene with taped joints, over plywood as required for structural shear, over conventional 2x6 framing, filled with blown-in cellulose, covered by 5/8" gypsum wallboard. The house will be both heated and cooled (A client mandate). We're assuming that the wall would dry to the inside, but...

Asked By Lydia Marshall | Mar 3 10
4 Answers
Best sealant for underground house walls

We have purchased an underground house; only south side face showing. We have removed 3 feet of dirt from the top and have had a backhoe remove dirt from all three sides so the french drain system can be replaced. What is the best sealant/insulation to put on these three walls? A company doing open cell foam spray tells us that's the best but I don't want that on top as I want to keep it for a patio. What would be the best for the top?
Thanks,
Kathy

Asked By Kathy Henthorne | Aug 11 09
6 Answers
We bought a property that has an old meat-packing house on it.

The walls of the packing house have cinder-block with 8" of styrofoam insulation. The main floor is concrete over an open basement with structural support. The ceiling has 8" styrofoam as we are putting a steel roof on as well. And what kind of 'green' lighting would you recommend?

Asked By sherri | Mar 8 10
10 Answers
How to find someone who treats mold?

My home has a mold problem that suddenly occurred and it needs to be treated. It is in my kitchen/hallway.

Asked By Sara | Mar 5 10
5 Answers
Does interior ceiling strapping defeat the effectiveness of fiberglass insulation?

I'm a remodeling contractor and am about to do another basement remodel. I will be insulating the walls with 2" of XPS, framing stud walls in front of the rigid foam, and then attaching drywall to the studwall. The underside of the slab is insulated, so I won't be laying foam and plywood on the floor of this project.

Asked By Justin Fink | Mar 5 10
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