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2 Answers

Insulation for a cathedral ceiling

I'm working out the details for an addition I'll be building next summer. I'm in northern Minnesota. I'll have a cathedrial cieling at a 10/12 pitch and I'm planning on using 2x12 rafters wo have the room for insulation. The room is 29' wide the direction that the rafters run.
From what I've been reading I don't necissarily need to ventilate the roof as long as I make certain to seal the space very well. I have a couple ideas I'm looking at for that and I'm looking to see if either of my potential ideas have any red flags against them and perhaps pros and cons between them.

In Energy efficiency and durability | Asked By Mark Larson | Dec 2 12
2 Answers

Garage door detail on FPSF

Doing a FPSF w/ an attached garage(heated) in zone 5a. Does anybody have a good detail for an overhead garage door where it contacts the slab? Have a few ideas in mind, but need something that will last. That is one nasty thermal bridge to contend with....

In Green building techniques | Asked By Todd Kalin | Dec 2 12
1 Answer

NYSERDA is producing entertaining videos

Here's a NYSERDA video explaining "whole house" principles:

More videos here:

In Energy efficiency and durability | Asked By Martin Holladay | Dec 2 12
1 Answer

Insulating a barn ceiling

I live in northern New Jersey. I am insulating the room above my barn. The barn is unheated. I am planning to insulate the floor from underneath and cover it with plywood.

My question is whether to use faced or unfaced insulation and if faced is recommended, which way should the facing face?
Thank you

In Energy efficiency and durability | Asked By Randy Aubrecht | Dec 1 12
5 Answers

Air leakage or just interior humidity / stale air?

I have a 1930s home in Sudbury, 4 hours north of Toronto, Ontario. Temperatures get down to -40 degrees C in the winter here. The home is an old log home. 2 years ago, I installed 3" polyiso on the exterior of the house, and replaced the windows with Fibertec, triple glazed windows, high SHGC on south face, mid-low on remaining orientations. I also chose fixed windows for better peformance on north and south walls, as prevailing winds are east-west.

In Energy efficiency and durability | Asked By Aaron Dent | Dec 9 10
7 Answers

Ideal roof overhang length?

I think I have decided on the wall assembly that I want to use but by the sounds of it it spend time concentrating on the wall but very little time on the roof.

I have read several books on sustainable design and affordable or low tax housing. My general plan was to build a rectangular house with a gable end roof on a 4/12 pitch. I had intended to use either a 16” or 24” raised heel truss with 2’ overhangs. I intended to use through fastened metal roofing. My design goals are one and only one roof line.

In General questions | Asked By Shane Fairman | Nov 30 12
2 Answers

Amercian clay and water (wall plans)

We're in Austin TX (Zone 2). The house has decent eves (3') but lots of high gables. Our climate is mostly dry, but with some humid periods and rain comes in large, sometimes driving, storms.

Our current wall profile (probably 50 years old) and, from inside -> out:

Concrete block (8") -> Stucco (very, very hard) -> Paint (lead based).

We have some newer sections with just concrete block, parged with Type S, unpainted. These were windows we made smaller.

Eventually we want this profile:

In Plans Review | Asked By James Howison | Nov 30 12
1 Answer

Tempering water for domestic hot water

HI, I’m looking to build an Insulated Raft or Frost Protected Shallow Foundation single story in zone 6. I have a few questions regarding waste water heat recovery and tempering incoming cold water for domestic hot water.

I am interested in a grey water heat recovery but since i’m not planning to build a basement so I can’t install the standard vertical mount heat exchanger.

In Mechanicals | Asked By Shane Fairman | Nov 30 12
4 Answers

When Alan Met Sharon (A U-value Romance) - YouTube Video


I question the use of marshmallow insulation in this wall section, though. Too many voids. I probably would have used sprayed-in cheez-wiz.

In General questions | Asked By John Semmelhack | Nov 30 12
5 Answers

Post Hurricane Sandy repairs: advice needed

Insulate new ducts? Bubble wrap or what kind? Water in crawl space solutions?

Hi, I have a small cape cod house on a lake, 2 blocks from the ocean in NJ, that was recently flooded by Hurricane Sandy. The seawater came 4' above ground level, 14" into the house.

There is a low dirt bottom crawlspace, which has water or is wet most of the time because the water table is so high.

In General questions | Asked By Sandy Sole | Nov 30 12
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