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1 Answer

Exterior Roof Insulation

I live in north west Louisiana. I've been searching for a way to insulate my ceiling/roof without covering the togune and groove cedar ceiling. The house was built int he late 70's as a camp so I guess they decided not to put an attic. The roof consist of sheathing and shingles on the exterior and the cedar planks on the interior. I like the existing cedar and don't want to cover it up.

In Energy efficiency and durability | Asked By Ron Inget | Oct 12 13
4 Answers

Will attaching 1" rigid foam to the inside of a stud wall create an effective thermal break?

I am getting ready to complete a timber frame project in Northern Minnesota that I started several years back. I left it with 3.5"stud wall envelope sheathed in OSB thinking that I would insulate with spray foam. Since then, I've read about thermal bridging and have come up with a wall system that I believe will address that issue, give me an acceptable R factor and not create a second condensation surface. That is: board & batten siding (locally milled tamarack), OSB, R-15 fiberglass, 1" rigid foam, 1/2" sheetrock. I would appreciate comments.

In Energy efficiency and durability | Asked By Wade Srock | Oct 12 13
2 Answers

Superinsulated garage doors -- again

I know garage doors have been debated quite alot already,
but i haven't found any mention of anybody trying to actually "add " insulation to an existing door

I was looking at residential and commercial garage door manufacturers website a few moments ago, amazed on how "their special" polyurethane achieve R16 at only 1.75"
( they must be onto something we do not know!! )

And i notice the lack of new solutions for cold climate situation other than
the 2" thick steel/poly/steel slabs they advertise as R18 , which is probably closer to R8-R10.

In General questions | Asked By Jin Kazama | Oct 10 13
11 Answers

Flashing on window sill: To be or not to be? That is the question

New construction - builder installed Marvin windows w/o flashing the sill, although Marvin calls for it. Is this acceptable?

In Building Code Questions | Asked By Elizabeth Croes | Oct 10 13
1 Answer

Spray-on housewrap

My contractor asked me to look into doing a spray-on housewrap instead of a normal wrap.
He said I could cut down on using insulated siding and in-house spray-in foam. I like the idea of the spray-on housewrap but not sure about its effect versus spray foam inside.

Any insight one way or the other on this subject. This is new construction.


In Energy efficiency and durability | Asked By Robert Martin | Oct 11 13
2 Answers

Where to put the fresh air vents from a HRV with dedicated ducting?

I'm about to install a HRV/ERV into a new construction in the Seattle area and was wondering where to put the fresh air vents inside the rooms.

Do they go in the floor / low on the wall or ceiling / high on the wall?

The manufacturer UltimateAir recommends putting them low, but I've read a lot of recommendations to put them high on the wall. The fresh air ducting will also include a water to air coil that will add some cooling in the summer.

Wouldn't it make more sense to put them high as the incoming air would usually be cooler than the room temperature?

In Mechanicals | Asked By Joerg Zender | Oct 9 13
0 Answers

Waterproofing slab on grade frost wall?

We are building a slab on grade addition to our house in Wisconsin, zone 6. It has a frost footing and wall which will be back- filled with sand. To match the aesthetics of the existing house, the exposed foundation will be rock faced cement block, with 4 inches of foam on the inside wall of the foundation (and 4" under slab and @ slab edges).

The WI code requires waterproofing of the frost wall. Our mason with 50 years experience doesn't think it is necessary, but the inspector does, so I'll seal it. I thought I'd use an acrylic product.

Any thoughts and recommendations?

In Building Code Questions | Asked By Edward Krause | Oct 10 13
2 Answers

I am looking for a green expert / net zero expert for my new construction home in central Iowa

Looking for a expert/guru/mentor for my new construction residential project. Build location is in between Ames and Des Moines. Goal: a healthy home, energy-efficient, self sustainable.

In General questions | Asked By Malinda Boyko | Oct 10 13
3 Answers

Adding more insulation to an attic with R-38 fiberglass

I have a 2200 SF raised ranch built in 1983, with another 1000 SF finished in the portion of the basement with 4' stem walls. The rest of the basement is unfinished. The heat is electric radiant throughout; on the main floor the heating cables are laid on top of the ceiling drywall. I've just moved in and the house was vacant for the previous two years, so I have no idea what to expect for heating bills.

In Energy efficiency and durability | Asked By Jonathan Bean | Oct 9 13
3 Answers

Provide make up air for a wood stove

Make up air

In Green building techniques | Asked By Thomas Williams | Oct 5 13
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