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4 Answers

Which attic configuration is best?

I am going to build a home in Melbourne, Florida, climate zone 9B or 10A depending on the source. The home will have wrap-around porch varying in depth from 6 – 10 feet around the majority of the exterior. I will be installing a white metal roof and cold formed steel trusses. I have read a fair amount of literature on the topic of attic/roof configuration, including papers, reports and forums. There are two configurations which I believe would perform the best energy-wise. The first is a vented attic with ductwork contained in the conditioned space below and insulation above the ceiling.

In Energy efficiency and durability | Asked By Trevor Bowden | Jun 30 13
1 Answer

Rigid foam board as a vent baffle

In a vaulted ceiling, if using one inch rigid foam board furred out a min of 1" to provide ventilation from soffit to ridge vent followed by fiberous insulation such as fiberglass batts ......is this proper? would the one inch of foam used as a vent baffle be prone to condensation in a cold climate or does this particular situation not call for the min R-20 of foam? thank you in advance for the help.

In Energy efficiency and durability | Asked By thomas muller | Jul 4 13
5 Answers

Best practices for minimizing roof penetrations?

My house will have a gable roof with standing seam metal roofing. I'd like to minimize the number of penetrations to reduce the potential for problems over the long term.

In Green building techniques | Asked By Steven Knapp | Jul 1 13
26 Answers

What are the REAL downsides of ICFs?

Let's say i've set eye on 2 building methods
( sorry if my view is always toward cold climate building ..bear with me )



I've read discussions on this board and other websites,
thought about it ..heck it was my first idea all along!!!
PERSIST building method has to be the most efficient type of building
for passive and or very low energy haus

( why is not everybody building that way on cold climates if it is the best method neway ??? )

But then if we introduce ICF in the discussion

In Green building techniques | Asked By Jin Kazama | Jan 7 13
2 Answers

Stud spaces as air ducts

Are there any code issues with using the stud spaces of interior walls (dry walled) as forced air ducts?

In Building Code Questions | Asked By Jerry Liebler | Jul 3 13
5 Answers

Low-pitch-roof and wall ventilation

I would appreciate advice and feedback on venting the walls and roof of a SIP house with a 1/2:12 pitch roof. 3/4" furring will provide the walls' rainscreen gap. Air space above the flat roof SIPs will be 24" o.c. 2x's with a 1"-to-11" taper.There won't be much stack effect, and I'm uncertain whether the venting at the top of the low-side wall will be drawing air in or out. I have attached a .jpg illustration. Thanks!

In Green building techniques | Asked By Mark McCain | Jul 1 13
3 Answers

Foundation drainage and exterior insulation


In Energy efficiency and durability | Asked By Steven O'Neil | Jul 2 13
19 Answers

Ducting a ductless minisplit

I have read of the problems with the distribution of hot air and cool air in well sealed and insulated houses, and I have a "boss" who dislikes the looks of minisplit indoor units. But we don't need more heat or cooling than a Mitsubishi Hyper Heat can provide.

In Energy efficiency and durability | Asked By Jerry Liebler | Jun 28 13
5 Answers

Asphalt shingles and unvented roof construction

For complex roof forms (dormers, valleys, etc.) that enclose living space (resulting in sloped ceilings & knee walls) I'm a big fan of unvented ("hot") roof construction, primarily because it seems difficult, if not impossible, to effectively maintain continuous, balanced ventilation from eaves to high points with such roofs. Also, there's a certain simplicity to keeping the building envelope out at the roof, with its advantages of keeping ducts and access panels all within conditioned space, and with its potentially simpler construction.

In General questions | Asked By Will Tinkelenberg | Mar 10 11
2 Answers

4-inch rigid foam applied to exterior, air barrier before vertical concrete?


In Green building techniques | Asked By Matt Tackett | Jun 29 13
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