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NetZero Energy Architects "Hybrid" Home Energy Design

Solutions that Reduce Home Energy Use While Increasing Quality and Comfort.
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The Old Yellow House Orin
Artist Recognition Award
Annapolis Passive House
Passive House
Annapolis Basement Energy
Marin Home & Garden Expo
West Coast Green 2010
Earth Day 2010
Home Performance Test
Fresh Air Ventilation
MechanicallyVentilated CS
Geo-Solar Thermal Energy
Crawl Space Case Studies
Design Build Partnership
FreeWatt - Cogeneration
Geo Thermal
Danville 2010
Alamo Remodel 2010
Alamo Residence 2010
Carmel 2009
Vert Ramp 2008
Lafayette 2007
Potrero Hill S.F. 2006
Lafayette 2006
Lafayette 2005
Caith Tree House 2005
Lafayette 2005
Lake Almanor 2004
Los Altos Hills 2003
Buddhist Spiritual Center
Los Altos Hills 2001
Wright Studio 2001
Bell Canyon LA 1999
Santa Monica Canyon1998
Oakland Hills 1997
Brentwood L.A. 1997
Japan 1996
Oakland Hills 1993
Beverly Hills 1995
Peter Falk B.H. 1995
Venice 1990
Solar Mansion B.H. 1989
Jellyfish UCLA 1985
Jellyfish Malibu 1985
Laser Jellyfish B.H. 1983
Solar Greenhouse Md. 1981
Private Study Gaudi 1980
U of MD. Daylighting 1980
Tree House 1965
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Crawl Space Facts
An 1890 Historical Landmark 
"Deep Energy Retrofit"
"The Old Yellow House" in Orinda California
The world's oldest Net Zero Home
A Passive Geo-Solar Home 


The potential for historical preservation of very old structures by minimizing infiltration (air leakage), a building code standard for indoor air quality, health, and structure preservation, can be accomplished through "GeoVentilation " of the subterranean structure. We can now allow historical dwellings to become energy efficient by making them air-tight. "We are particularly excited about old historic buildings."  The Old Yellow House, currently a historic landmark home in California, that we have renovated to passive house standards, as well as exceeding the Net Zero status.  Actually, this 1890 six bedroom residence will become a "Net Positive" dwelling producing excess power for its future guest house or electric vehicle.

When a “Basement Energy System” is placed within  a Passive House energy recovery ventilation system, it requires very little additional power to operate. Passive houses consumes 90% less energy that typical homes of the same size. With our Geo-Solar hybrid “home as a system,” we predict performance to be close to 95% annual energy reduction. 

Our earth / geo air conditioning system, based on the calculations from the energy modeling program, shows no cooling required. In fact with night time and periods of cooler weather, the system can over cool, allowing the thermal mass to fly wheel or drift for an extended period of time during sweltering hot muggy weather, therefore never requiring cooling, because of the innovative well water evaporative cooler. The Geo Cooling contribution, and the hybrid PV/Ta solar collector with adjoining thermal storage, qualify the entire cost of the system to be eligible for the federal energy tax credit of 30%.



How Our Geo-Solar System Works


Integrated Ventilated Photovoltaic Skylight (PVta)



Expressing the Future within the Past


Increase Building Mass within the Ventilation Air Stream


Thermal Storage Labyrinth


A Geo-Solar System



Original Computer Model



Geo Solar System Schematic




Energy Modeling of the Well


The 27' Deep Well
 A Geo-Solar Ventilation System
 Integrated Evaporative Cooling Piping
 The Geo-Cooling System Well and Storage Chambers 
New Reinforced Slab Buttressing the Stone Walls  

Salvaging the Stone Foundation
Back to the Original Color
 Confirming Original Color
Missing Redwood Molding 
Original Siding Re-Installed
Original and New Cornice Detail
Original Overhang and New Re-installation Detail
 Before and After Progress
Re-installation of Refurbished Original Siding
Acoustical Isolation Complete
Progress Sound Isolation Material Installation
Ventilated Façade Detail Diagram
Rubber "Limp Mass" Over Battens Creating a Ventilated Façade
Exterior Insulation Secured with Sound Isolation Bushings
Roof Framing Complete
Battens Secured with Isolation Bushings 
Roof Overhang Framing Over Insulation
Complete Isolation w/ Sound Bushing Preventing Vibration Conducting Through Structure
Rubber Sound Isolation Detailing
 Acoustical Engineer Listening to the structure
6" Polyisocyanurate  (closed cell) Insulation
Exterior Insulation with Staggered Joints
 Interior Storm Windows effective "Triple Glazing"
Window Unit Set
Air Sealing for an "Air Tight" Enclosure
Radiant Barrier / Heat Mirror Plywood
All Parts Dismantled & Refurbished for Reinstallation
A Chainsaw Retrofit / Thermal Bridge "Free"
Geo Ventilation for Passive Cooling 
Earth Coupling Beneath the Thermal Envelope
Lifting the House & Preserving the Hand Dug 27' Deep Well
"Old Growth" Redwood Structure