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4 Answers

Dripping walls and wet sheathing in new house

A friend of mine has just built a log house with standard 2x4 (or 2x6) wall framing on the second floor in zone 6-7. The walls and ceiling have been insulated (roxul and foam in the walls and pink in the ceiling) but they have not yet put up a polyethylene vapor retarder. They turned on the heat this week and the walls started to drip and the sheathing behind the wall insulation became wet. Essentially, the moisture in the house turned to vapor and quickly condensed on the cold surfaces of the house.

In Energy efficiency and durability | Asked By jessie pratt | Dec 6 12
6 Answers

Leaky house and oversized new HVAC systems?

We bought the farm, so to speak in the deep South - a 1-1/2 story house built in 1950. We are looking for thoughts on dealing with a very leaky house with historic ductwork and new, oversized HVAC systems.

In Energy efficiency and durability | Asked By Sue Davis | Dec 5 12
4 Answers

Best insulation for a barn that will be converted to a workshop

I have a 2 story 24' X 36' barn built on a concrete slab. It is constructed with 6x6 posts, 8' apart. The exterior is board and batten. There is no insulation and no interior wall; i.e. the interior walls are the board and batten siding. Although it is well constructed, there are a few areas were moisture could enter the building. What would you recommend to insulate this type of building?


In Energy efficiency and durability | Asked By Samuel Baum | Dec 5 12
3 Answers

Green roof energy savings

As a project for school, I am looking at installing a green roof on a building on the Vanderbilt University campus. We are looking at installing an extensive (6" deep soil or less, with simple plant growth) for a 1500 square foot area that is currently black top. It is a single story building, that is in use 24/7 by students. What would be the estimated yearly energy savings for such a project? This information needs to be approximated for the proposal. Thanks and blessings

In Energy efficiency and durability | Asked By Andrew East | Dec 5 12
6 Answers

Resource for building Passive Solar

HI, I am planning to build a passive solar home in the upper Midwest. There are not any builders in my area that build this way. Besides reading articles on this site, does anyone have any suggestions on how I can accomplish this project? I want to build with ICF's. My concerns would be making sure I have the proper insulation under the basement and in the roof, the right heating for my home and area, the right windows and ventilation system.

In Green building techniques | Asked By Kami Kline | Dec 3 12
3 Answers

Tyvek detail around windows

Help, the windows are here! so i'm all geeked out to check them out and install them. we wrapped the entire house, including the rough openings, in tyvek, BEFORE the windows arrived. our plan was to cut open the wrb, flash the sill with a piece of bevelled siding and flexwrap, then install the window. tyvek recommends making an i-cut in the wrb (one vertical cut in the middle from header to sill and two horizontal cuts from side to side along the header and sill) and wrapping the flaps of the tyvek around the sides of the window and fastening them.

In General questions | Asked By erik olofsson | Dec 5 12
1 Answer

Are heat blocks effective without dead air space?

I'm working on installing STEP warmfloor radiant heat, and I'm looking for a material to install under the heating element that will limit the amount of energy lost to the crawl space under the house.

So far I've only been able to find products aimed at hydronic radiant heat systems, rather then the heat pads like STEP, and those are all to be installed under the house, rather than on top of the subfloor. Is there a product that i can install directly under the element?

In Energy efficiency and durability | Asked By Evergreen State College | Dec 5 12
3 Answers

Buried fresh air intake

A local TV station ran a story about a recently built energy efficient house. It was in a rural area and not on a city lot. They were short on details of what made the home energy efficient. They said wall and floor were concrete so it sounds like they have an ICF house. There is a solar panel array. Last summer the ac cost $3 a month. No mention if that was total energy use.

The homeowner claimed "it does cost anymore to build" and she didnt know why more people didnt build ee homes.

In Energy efficiency and durability | Asked By Robert Hronek | Dec 5 12
0 Answers

What kinds of waterproof membranes can I use over the top of radiant in floor heat?

I'm currently working on a remodel of small dorm building at The Evergreen State College in Olympia WA. We're planning on installing STEP warmfloor radiant heat, but we have some concerns about installing it in the bathrooms.

Is there a kind of membrane we can install over the heating element, under either laminate or tile that will protect the element from water damage but can also withstand the heat?

In Green products and materials | Asked By Evergreen State College | Dec 5 12
15 Answers

Zone 5 - Different wall options

Building in Nebraska (Zone 5). Builder proposed 2x6, 1/2" spray, then fiberglass batts.

I understand 1/2" sprayfoam would raise condensation issues. In meeting with the builder soon, I will propose three alternatives:

-2x6 wall but 2" sprayfoam, then fiberglass batts/blown fiberglass/cellulose, depending on price and availability.

-2x6 wall and 2" rigid foamboard on exterior, then fiberglass batts/blown fiberglass/cellulose (my builder has not done this before and may not be comfortable with this)

In Green building techniques | Asked By Cameron Guenzel | Dec 4 12
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