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4 Answers

Hi all,

A friend has left over rigid backed foam insulation and asked me my thoughts on using it to completely fill the rafter space (no air space) for a portion of a roof on small houseboat. He want to use two layers of the foam (both foil backed). Orientation of foil? Bad idea altogether?



In Green building techniques | Asked By Daniel Weaver | Nov 15 11
1 Answer

I've read several postings in your blog on the subject of roof venting and cathedraled ceilings but haven't found an answer yet for my project. It's a half story room above a garage that is completely unfinished on the second story. It has 5' tall walls on the eave sides, built on top of a wooden I-joist floor system which is insulated with R-38 fiberglass. The roof is a 10/12 pitch, gable end on one side and attached to the existing house on the other.

In General questions | Asked By Marc Beatty | Nov 15 11
1 Answer

Can anyone recommend an affordable device to record temperatures?
Want more than just the daily high and low, maybe once per hour.
I have built several passive solar homes, some with high thermal mass
and some with no additional mass. Would like to monitor temerature swings.


In General questions | Asked By Richard Patterman | Nov 15 11
4 Answers

Hello Lucas
OK. we know you are busy building, but we need updates!...we need details!...we need pics!!!!

In General questions | Asked By Garth Sproule | Nov 13 11
1 Answer

Hi All,

I am in the process of re-modeling the 3rd story of a home in Oregon (zone 4 or 5). I opened the ceiling to create a cathedral ceiling. I have never insulated a cathedral roof so I have spent a few weeks reviewing all the post here and think I have the solution, but I would like some input if possible. First of all, there may be better solutions, such as spray foam, but budget constraints dictate the need for coming up with a workable and affordable solution.

In Energy efficiency and durability | Asked By David Baker | Nov 15 11
3 Answers

My 1950's apartment has a large window. They are about 10 feet long and 4 feet high. There is a fixed center panel and a casement on either end. Single pane, metal frame. The frames are a bit wracked out of square, probably from earthquakes over the years, and won't close fully. (coastal southern california mild climate but winter nights are in the 40's with a medium Santa Ana wind ).

In Energy efficiency and durability | Asked By Brenden McEneaney | Nov 14 11
4 Answers

I live in Corpus Christi, TX, a hot & humid area that occasionally gets hurricanes. In order to get windstorm insurance, we must purchase it from the Texas Department of Insurance (TDI). The Texas Windstorm Insurance Agency (TWIA) is the organization tasked with determining the "approved" installation methods for both roofing & siding.

It supersedes all local building codes. The local building inspection department requires the homeowner to furnish an inspection report from the TWIA that installation is in accordance with their "approved" methods.

In Building Code Questions | Asked By Ken Ackerman | Nov 14 11
4 Answers

I've looked at several BSC basement insulation recommendations, and they all use foam next to the concrete wall...looks great, but I don't like foam.

Would a wood stud wall, physically separated from the cement, insulated with fiberglass, rockwool, or even cellulose, detailed according to the ADA, and painted with something vapor permeable be scientifically sound?

In Energy efficiency and durability | Asked By Richard Baumgarten | Nov 11 11
2 Answers

I have a two-story house in Atlanta, GA, built in 1984.

I have noticed my supply and return registers have some air drawing in them on the second floor. I have a sealed gas furnace, 95% AFUE.

The HVAC vendor has told me the house draws air in as well. I have caulked around all registers and masticed all areas of ductwork and plenum. All my gas appliances are new furnaces (2), Tankless water heater, and gas range.

Question #1. If a house has a "stack effect" why am I seeing this happen?

Question # 2. Should I be concerned about this?

In General questions | Asked By Scott Razzino | Nov 12 11
8 Answers

I am having trouble calculating water heater recovery efficiency.
Specifically, I do not know how to calculate or determine RE for a 90 or 95% Thermal Efficiency gas storage tank water heater, examples Vertex 100k unit or State GP 650 76k or 100k unit.
Since these units are over 75k BTU input, they are classified as commercial water heaters, do not have energy factors specified by law, and I am now simply trying to learn how to calculate their recovery efficiency RE.
Any help would be greatly appreciated.

In Energy efficiency and durability | Asked By Andrew Dunn | Nov 5 11
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