[GSBN] Straw-Bale Blower Door and Infrared Test Results
dan at dsaarch.com
Fri Dec 24 08:57:58 CST 2010
David, that's about what I thought, what do you think about the
likelihood of bale walls meeting the 0.6 standard?
Principal - DSA Architects
1107 Virginia St.
Berkeley, CA 94702
dan at dsaarch.com
On Dec 23, 2010, at 11:27 PM, David Arkin, AIA wrote:
Hi Dan, David E.:
Sierra Energy Professionals (SEP) say:
> When the house pressure was at a 50 Pa difference relative to the
> exterior, the flow of
> air infiltrating from outside into the building envelope was
> measured to be 617 cubic
> feet per minute (CFM).
Based on "9592 cf house", 617 CFM = 37,020 CF/hour, or 3.8 times the
volume of the house:
Flow @ 50 Pa Air changes per hour (ACH) @ 50 Pa
617 CFM 3.8
If the house were tighter:
160 CFM 1.0 (probably about what John's house is)
96 CFM 0.6 (Passive House (PH) certification threshold)
So house is 6.4x leakier than PH threshold. We've done a passive
house project since this one, but none bale ... yet.
However, this is an off-grid home, with a combined passive and active
hot water heating system, storing heat in an insulated sand bed, with
electricity from a photovoltaic system. So we're wasting some of that
free energy from the sun ... I think we can live with that!
John, it's our 'typical' system of 14" I-joists at 7' to 10' on
center, with 3-string rice bales on edge, PISE finish.
More cheer to y'all,
On Dec 23, 2010, at 9:42 PM, Dan Smith wrote:
> David and Anni, thanks for sharing this, it is a treat.
> What's the air change per hour at 50 Pa?
> Happy Holidays,
> Dan Smith
> Principal - DSA Architects
> 1107 Virginia St.
> Berkeley, CA 94702
> 510.526.1935 x101
> 510.526.1961 fax
> dan at dsaarch.com
> On Dec 23, 2010, at 2:48 PM, David Arkin, AIA wrote:
> Hello Fello Baleos Worldwide:
> Since this list is particularly alive today, I'm taking the
> opportunity to share a Christmas treat.
> I attach here (gosh, can I attach to this list?) a report on a
> Blower Door and Infrared Camera test done on a 900 sq. ft. (85 sq.
> meter) home in the foothills of the Sierra Nevada mountains.
> In particular, dig this quote from Michael Ukraine of Sierra Energy
> Professionals: "Any doubts that I had about straw bale or SIP
> construction are thouroughly gone after conducting these tests.
> This is definitely the tightest and best insulated house I have ever
> The photos are quite illustrative, but certainly say that the bale
> walls in no way constitute a weak link in a tight or thermally
> superior building. Don't ever let anyone try to tell you
> otherwise. We raise a glass to y'all, and wish you an excellent New
> David and Anni
> <Straw Bale House Photos 2010-10-18.pdf>
> * * * * *
* * * * *
Arkin Tilt Architects
Ecological Planning & Design
David Arkin, AIA, Architect
LEED Accredited Professional
CA #C22459/NV #5030
1101 8th St. #180, Berkeley, CA 94710
"There is no way to peace. Peace is the way."
— A. J. Muste
GSBN mailing list
GSBN at greenbuilder.com
-------------- next part --------------
An HTML attachment was scrubbed...
More information about the GSBN