Mother Earth Living

Aggressively Passive: Building Homes to the Passive House Standard

Houses built to the Passive House building standard use as little as 10 percent of the energy that standard homes use. The best part about them, though, is how good they feel to live in.
By Carol Venolia
January/February 2011
Add to My MSN

Catherine O’Neill’s California home is the first U.S. retrofit to be certified by the Passive House Institute U.S.
Photo By Ned Bonzi
Slideshow


Content Tools

Related Content

Wabi-Sabi Wednesday: Clean Enough

Wabi-sabi is never slobby, but we can allow ourselves to stop trying so hard and just appreciate our...

Building the NewenHouse Kit Home: Living in a Passive House

Guest blogger Sonya Newenhouse tests the performance of her new Passive House by not turning on the ...

A Florida Home Cooled Without AC

This home in the Florida Keys captures prevailing breezes and takes advantage of passive cooling tec...

5 Housekeeping Tips from Mother Earth News, 1970

These tips mined from the second issue of Mother Earth News, published in 1970, will make your house...

Imagine spending a long Illinois winter in a cozy house with no cold corners or drafts—and heating bills half the norm—or sailing through a sultry Louisiana summer in cool comfort with bills that cost a fraction of the neighbors’. Passive House, the latest set of building standards sweeping North America, uses seven simple principles to make these housing dreams come true.

Passive Houses are so well designed, insulated, sealed and ventilated that they require as little as 10 percent of the energy standard homes use for heating, cooling and lighting. A tight envelope (roof, exterior walls and floor) and thick, heavily insulated walls keep winter cold and summer heat at bay with little reliance on furnaces and air conditioners. In winter, Passive Houses hold in heat from the sun, inhabitants’ bodies, lights and appliances. In summer, they keep cool air in and hot air out, though additional cooling may be needed in very hot, humid climates. Energy-recovery ventilators (ERVs) circulate fresh air for even temperatures and humidity.

Though the movement traces its roots to the American superinsulated house movement of the 1970s, the Passive House principles were further developed and codified by German professors Wolfgang Feist and Bo Adamson in the 1980s and 1990s. Using the standards of the Passivhaus Institut (PHI) founded by Feist in 1996, thousands of European homes have been built or remodeled, and many provinces and cities require projects built with public monies to achieve PHI certification. Architect Katrin Klingenberg brought the Passive House movement to the United States, co-founding the Passive House Institute United States (PHIUS) with builder Mike Kernagis in 2008. Close to 60 Passive House projects have been completed or are underway around the country.

Selfish Altruists 

In Europe, the Passivhaus Institut has worked out many of the system’s kinks, but the United States encompasses a different range of climates, aesthetic tastes, and financial and property practices. Every U.S. Passive House breaks new ground. With Passive House construction costs at 6 to 15 percent above average, early adopters must be committed to long-term, deep energy conservation and be willing to work out the bugs for the rest of us.

Margaret and Gregory Stanton, who built a Passive House in Urbana, Illinois, don’t feel altruistic. “We’re selfish,” Greg jokes. “We’re free from volatile energy prices.” The Stantons love their thick walls and deep windowsills, energy savings and the absence of drafts. In response to Urbana’s cold winters and hot, humid summers, the Stanton house has R-87 roof insulation (20 to 24 inches of loose-fill cellulose), 18-inch-thick R-64 walls and a thick slab floor insulated to R-51. Direct solar gain provides much of their heat, backed up by a heat pump and an inline heater in their ERV. The Stantons collect rainwater to irrigate their garden, use solar-thermal panels to heat their water, and salvaged much of the wood from the original house on their 2.5 acres.

Passive Houses are popping up all over. “Passive House has exploded in this country,” Kernagis says. “In 2008, there were 15 certified Passive House consultants in this country. Now there are 275, and we’re training more.”

Kernagis has seen public and professional opinion about Passive House evolve from apprehension to growing acceptance, and he hopes that someday the standard will be written into building codes and municipal mandates. “People resonate broadly with our building energy metric,” he says.

The standard’s best advocates, Kernagis says, are Passive House homeowners. “They’re just so happy, and they want to tell people about it.”

A Passive Retrofit 

In Sonoma, California, Rick Milburn of Solar Knights Construction is using the Passive House standard to upgrade Catherine O’Neill’s home. The 1962 bungalow—the first Passive House Institute U.S.-certified retrofit—uses about 70 percent less energy than its neighbors. “People think these things are complicated,” Milburn says, “but they’re supersimple.” The O’Neill home is insulated to a standard unusual in California: R-74 roof, R-31 walls, and R-12 to R-20 floors (Energy Star recommends roof insulation of R-30 to R-60). A solar-thermal array heats water and spaces. “In California, we don’t need furnaces or air conditioning if we build right,” Milburn says. “If we just lower the load, we don’t have to spend trillions on our utility grid.”

Coolin’ on the Bayou 

University of Louisiana architecture professor Corey Saft used the Passive House standard when he built a rental property known as 204House on the lot he owns next door to his Lafayette home. He admires the standard for its simplicity, calling it “an understandable, knowable metric.”

Renters have lived in 204House for almost a year. “The renters love it,” Saft says, “and we’ve shown that not only can Passive House principles work in this climate, but that they also work financially.” Despite its 10 percent higher-than-average construction costs, 204House’s market-rate rental income covers expenses, with money left over for repairs. In fall, spring and part of the winter, the home’s utility bills are extremely low—averaging less than $10 a month. Saft monitors the house’s performance and tweaks ventilation to optimize comfort and energy efficiency.

Resources 

Information 

Passive House Institute United States (PHIUS) 

Passivhaus Institut  

Services 

Corey Saft, RA, LEED AP
Lafayette, Louisiana 
(337) 482-5325
csaft@louisiana.edu 

Lail Design Group
St. Helena, California
(707) 963-1565
www.laildesign.com 

Solar Knights Construction
Napa, California
(707) 975-6912 

Further Reading 

Homes for a Changing Climate: Passive Houses in the U.S. by Katrin Klingenberg, Mike Kernagis and Mary James

Recreating the American Home: The Passive House Approach by Mary James

Low Carbon Productions   

Architect Carol Venolia, co-author of Natural Remodeling for the Not-So-Green House, writes Natural Home’s “Design for Life” column.  


Previous | 1 | 2 | 3 | Next






Post a comment below.

 








Subscribe today and save 58%

First Name: *
Last Name: *
Address: *
City: *
State/Province: *
Zip/Postal Code:*
Country:
Email:*
(* indicates a required item)
Canadian subs: 1 year, (includes postage & GST). Foreign subs: 1 year, . U.S. funds.
Canadian Subscribers - Click Here
Non US and Canadian Subscribers - Click Here

Subscribe to Mother Earth Living!

Welcome to Mother Earth Living, the authority on green lifestyle and design. Each issue of Mother Earth Living features advice to create naturally healthy and nontoxic homes for yourself and your loved ones. With Mother Earth Living by your side, you’ll discover all the best and latest information you want on choosing natural remedies and practicing preventive medicine; cooking with a nutritious and whole-food focus; creating a nontoxic home; and gardening for food, wellness and enjoyment. Subscribe to Mother Earth Living today to get inspired on the art of living wisely and living well.

Save Money & a Few Trees!

Pay now with a credit card and take advantage of our earth-friendly automatic renewal savings plan. You’ll save an additional $5 and get six issues of Mother Earth Living for just $14.95! (Offer valid only in the U.S.)

Or, choose Bill Me and pay just $19.95.