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4 Answers

Rigid insulation on exterior walls with high interior humidity

I built an addition on my house that includes a solar thermal array on the roof that heats an endless pool in the addition. The existing house is brick, so when i poured the foundation (foam blocks), i included a 4" brickledge. i have not finished the exterior yet, and am rethinking my options. I am in zone 6b. The construction is 1/2" sheetrock over conventional (not staggered) 2x6 studs with faced fiberglass bats in the stud cavities. exterior sheathing is 7/16" osb. finally, tyvek house wrap.

In Green building techniques | Asked By norm rostocki | May 25 12
8 Answers

How do I place baffles for cellulose attic insulation?

I am in zone 5 and have a house with a hip roof and a wide overhang. The house has about 3 inches of rock wool insulation and I would like to add enough cellulose to raise the R value to 60.

The top plate of the side walls is about 12 inches above the attic floor joists. When the rock wool was blown into the attic, apparently in 1961, newspaper was stuffed into the top of the wall cavities to prevent the rock wool from falling down into the wall. There are vents in the soffits at the eaves, outside of the walls.

In Green building techniques | Asked By Gregory Worrel | May 24 12
5 Answers

Air intake for a 70 year old Cape Cod with knee walls

I have a 70 year old Cape Cod with a finished upstairs. A few years ago a steel roof was applied over the existing roof. The contractor put in a ridge vent but I have no air intake. I have 2*4 framing with 1" insulation. What suggestions do you have for getting some air intake into this space ? Gable vents ?

In GBA Pro help | Asked By Brenda Nash | May 25 12
7 Answers

Unheated Home Dangers?

In general, what can happen if I leave my home unheated in the winter? Sounds like the green thing to do at first blush... Zone 6. Lots of passive solar windows on the south side of all three floors: Walk out basement, main floor, and attic floor.

The house is well insulated, vented, and dehumidified. Soils are well drained. Basement has 2in of xps on the outside below grade.

Pex lines will be blown out dry before summer shut down.

Thanks, Steve

In General questions | Asked By stephen edge | May 18 12
1 Answer

Rigid foam on the outside - worth it?

I've got quite the opportunity to improve my home's energy efficiency as we need to replace both our siding and our windows which are both original to the house. We had a mild winter here in the northeast this year and our propane usage was way too high. The new windows will be vinyl double pane low-e replacing windows original to the house which were simply popped in without insulation or any regard to energy use. Here are the details of the existing construction, and then some of the struggles I am facing with the different options which are out there.

- 2 story 1800 sqft colonial

In GBA Pro help | Asked By Paul Krsiak | May 24 12
7 Answers

Where do I place vapour barrier in relation to basement slab insulation?

I realize this question has been answered in numerous posts previously; however, our mechanical design involves using Insulworks insulation in the basement. Where and how do you suggest I place the vapour barrier if it is to be added on top of the insulation?

Here's the Insulworks product which involves using staples and is designed for the tubing to snug into grooves. http://www.amcfoam.com/PDFs/Insulworks%20general%20spec_web.pdf

Also, please forgive my ignorance, but why is it important to put the vapour barrier above the insulation and not immediately below it?

In Mechanicals | Asked By Jane Smith | May 23 12
2 Answers

How can I seal DensGlass (exterior drywall)?

I am using DensGlass on the exterior of my home (urban infill lot with zero clearance). I will be wrapping the exterior with Tyvek. I am thinking of sealing the joints of the DensGlass also. Is this overkill? What should I use to seal the DensGlass?

In Energy efficiency and durability | Asked By Charles Eichenlaub | May 23 12
2 Answers

Moisture Concerns when Sealing Air Leaks in a Brick and Block House

I'm working on a brick and block constructed house in south east Pennsylvania. The house was built in the 60's and does not have any insulation in the walls. The cross section of the wall consists of 4" of brick, then 4" of block, then 1"x3" furring strips, then drywall. The cavity created by the furring strips basically creates an air chute that runs from the basement to the attic.

In Energy efficiency and durability | Asked By Victor Burgos | May 23 12
1 Answer

Semi-conditioned space--is this an obsolete term?

I think of semi-conditioned space as within the thermal envelope but is not kept at the same temp as other space. An example would be a attic with insulation at the roof line or an unfinished basement that has minimal HVAC use.

In General questions | Asked By Robert Hronek | May 23 12
2 Answers

Hi, I need to have my windows replaced and eventually new siding.

Which way should go first, get the siding done or replace the windows? Thank you

In General questions | Asked By Holger Herrmann | May 23 12
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