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0 Answers
Advice for rebuilding in central Oklahoma?

Two degrees of separation from two of the many who lost homes in the recent tornados near Oklahoma City; wanted to tap the collective intelligence to work through how to 'build back better' (or retrofit surviving homes for resilience); both in terms of 'what', and 'how'; espcially, what is locally appropriate / cost effective, specific technical resources, etc., given the unique (and extreme) conditions in OK (tornado, fire, hail, and recently earthquakes...!)

To start the conversation (I will also work on answering my own questions here as I find more information):

Likelyhood of anothe

Asked By David Gregory | May 24 13
23 Answers
Cold sheathing question

Martin, I read your article on cold sheathing. I'm still not clear on one point: how do you know if the sheathing is wet due to the sheathing being cold and taking on moisture or the sheathing being wet due to vapour making its way from the interior of the house?

Asked By erik olofsson | May 22 13
0 Answers
Will my insulation plan work??

I am in the course of remodeling an 1860's balloon framed farmhouse in NE Pennsylvania. I am currently reinsulating the attic.It originally had only R-19 fiberglass insulation in it which had dicolored due to numerous air penetratrions. I was able to score salvages 1.5" felt covered polyiso board (came from a torn down factory) for very cheap and have purchased a closed cell spray foam kit.

Asked By Ben Hardy | May 23 13
4 Answers
Spray foam layer over board foam in Northern Zone 5a?

Mr. Holladay once wrote of rafters, "Yes, you can combine rigid foam and spray foam if you want to save some money. I would be inclined to install the layers of rigid foam first [I, Gordon, assume this means the rigid foam would go against the roof decking] -- cut undersized, and with canned foam sealing the perimeter of each rectangle -- and cap everything with spray foam [I'm seeing this as under the rigid foam and further away from the roof] from a contractor's truck."

Asked By Gordon B | May 23 13
4 Answers
Blower door questions

We are about to perform a blower door test on our small 650 sq. ft. new construction house. I have four quick questions:

1. We used T&G OSB and Siga tape for our air barrier, and i think we did an extremely thorough job detailing it. the house is not quite complete, however. for example, the clothes dryer is not installed, some of the joints in the hrv ducting in the crawlspace have not been sealed, the drywalled window returns have not been latexed to the window frames, etc... will these items have a significant effect on the test results?

Asked By erik olofsson | May 23 13
7 Answers
On average in New Mexico what is the cost per square foot to build a completely green home with the best insulation?

On average in New Mexico what is the cost per square foot to build a completely green home with the best insulation? It should be a passive solar home.

I need this information for insurance purposes in case I am in need of total reconstruction due to complete loss of our current home.

Asked By Leah Popp | May 22 13
2 Answers
Underlayment to use with hardwood

Hi,

Wondering what the opinion is on an underlayment for a hardwood floor.
From what i understand the main reason for an underlayment would be to have Vapor retarder (not barrier!) to slow the water vapor (if any) from passing thru the hardwood to fast which could possobly cause cupping and other issuies. Please add or correct if i am wrong.

Stackup:
slab > 6mil poly > 1" polyiso rigid foam > 5/8 advantec.

I think the advantec has a perm rating of 1-2

Asked By mark kessler | May 22 13
4 Answers
A-Frame re-roof - what type of (if any) air barrier?

I have an A-Frame (steep pitch cathedral roof) built in 1975. It is an unvented roof. Region 5, southern NH. It needs new shingles. The existing roof from inside out is:
5" x 14" laminated rafters 14’ OC
2-1/2" thick T&G decking
2" rigid insulation
Asphalt shingles nailed through insulation to deck

Removing the old shingles will harm the existing insulation, and I can find no existing air barrier. The roof is leaking.

The proposal under consideration is:
Remove existing shingles and insulation
Install air barrier to deck

Asked By BIll Berzins | May 22 13
2 Answers
Where should I put the foam in this roof?

Zone 4 marine. I'm pondering insulation strategies for cathedral ceilings.

In the past we have used typical cardboard baffles and either batts or blown in FG. Recently we did a small project where we cut and fit 2" polyiso for the baffles, with the usual 1" vent space above and foamed the edges, my theory being that this will reduce wind-washing of the fiber insulation and improve air-leakage performance. We also did one with 6" of solid polyiso where there was only 2x8 rafter space available.

Asked By David Meiland | May 22 13
6 Answers
Insulating or NOT insulating the basement slab

I previously had asked about the potential of constructing a rudimentary geothermal basement by purposefully NOT insulating the masonry walls of a basement. Martin pointed out that the ground temps in NY/NJ/CT in winter at the surface are freezing and not until something like 48 inches are they above freezing, say around 40 to 45 degrees? Thus making it clear the walls should be insulated. But what about the the floor slab? Assuming a depth of say 9 feet at the slab's underside, would this not be a constant 55 degrees or so? Thus be warming in winter and cooling in summer?

Asked By Sal Lombardo | May 20 13
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