This document provides an overview of Passivhaus and discusses its application in California. It summarizes that Passivhaus is a super-insulated and airtight building standard that is significantly more efficient than Title 24 requirements, with wall and roof insulation R-values that are 2-3 times higher. Several completed Passivhaus projects in California are mentioned, including both new construction and retrofits, and some lessons learned are provided around foundation insulation, overheating issues, and the importance of details and flashing. Monitoring studies have found Passivhaus projects in California perform as predicted in terms of energy efficiency.

1. Half-Assive or Fully-Passive
Talking chicken about Passivhaus and
how it works in California
Bronwyn Barry, Assoc. AIA, CPHC
One Sky Homes & Passive House BB
PHCA President
2012

2. What’s on the menu
A Passivhaus overview
How does it stack up?
California Projects
A few lessons learned
Details, details, details
Why chicken?

3. Passivhaus Overview
Super-insulated
Airtight
No Thermal Bridges
Comfortable
Very efficient
(This drawing by Dan Johnson)

4. Efficient compared to what?
Source: Numbers given by Mike Eliason on Bruteforcecollaborative Blog post

5. And what about Title 24?
80
70
60
50 Typical T-24 Project R-value
(hr.ft2°F/BTU.in)
40
PH Project R-value (hr.ft2°F/
30 BTU.in)
20
10
0
Windows Walls Roof Floor Total
Source: Values based on PHPP for one project in Albany, CA, 2010, by Bronwyn Barry, CPHC.

6. Who’s building this in CA?
Retrofits:
O’Neil Res, Sonoma
CLAM 1, Point Reyes
James Res, Marin
Tahan Res, Berkeley
Other retrofits underway in:
Oakland, Portola Valley,
Sunnyvale, Santa Rosa, Los
Angeles, Santa Cruz and more…

7. Who’s building this in CA?
New Construction:
Zen Center, Muir Beach
Zero Cottage, SF
Pomona St, Albany
Lemon St, Menlo Park
Cottle Res, San Jose
CLAM 2, Point Reyes
Project Green Home, Palo
Alto

8. A few lessons learned
• ‘Outsulate’ your walls for best
forgiveness factor and performance
• Use triple-pane windows (for now)
• Foundation insulation is key
• Edge of slab insulation is critical
• Overheating is our biggest issue
• Religion relies on faith, everyone
else bring data! (With thanks to Danny Parker)

9. The details matter
THERM is wonderful
(and free)

10. But the basics remain
And flashing is
still important

11. And the results are in
LBNL Study monitored
Ten Deep Energy Retrofits
(Including two PH
projects)
Both found to perform
AS PREDICTED
Source: Brennan Less & Jeremy Fischer
Lawrence Berkeley National Labs

12. So can we now talk turkey?
Illustrations by Bronwyn Barry for The Essential Urban Farmer,
written by Novella Carpenter and Willow Rosenthal
and published by Penguin in Dec. 2011

13. Where to learn more
www.passivehousecal.org
THANK YOU
Bronwyn Barry, Assoc. AIA, CPHC
One Sky Homes & Passive House BB
PHCA President
2012