Three years from now, in the year 2020, every new house built in California will be required to be “net zero” energy. Meaning that it will be required to harness at least as much energy as its occupants will use over the course of one year. Municipalities are scrambling, energy engineers are fidgeting, and residential developers are nervous over this impending regulation, which is creeping up on us like the San Andreas fault.
“We should be designing net zero buildings now, not in two years from now,” says Eve Reynolds, principal of the Silver Lake firm, Arcolution. “Did you know that there is a building standard that has been in use for over twenty five years throughout the world, which by definition, is net zero?”
She is referring to “Passive House,” the building standard imported from Germany which provides a very well-insulated, super-tight building construction with continuous ventilation, assuring the healthiest and most comfortable interior environment. The efficiencies of this standard minimize energy devoted to heating and cooling the space, thus “reducing energy consumption of buildings by up to 80%… When coupled with renewable energy systems, such as solar, Passive House puts zero energy buildings within reach,” claims Passive House California, a leading proponent of today’s highest energy standard.
In turn, this allows for a much smaller solar photo-voltaic installation than would be used in standard construction. The roof-mounted solar PV array is sized to provide the occupants’ entire electric load for the year, thus making Passive House the go-to net-zero energy building standard.
“Arcolution is poised to accommodate all zero-energy residential projects, not in two years, but today: single family dwellings, multi-unit housing, residential additions and simple remodels. We say, why wait until the year 2020 to get your net-zero game on when we are doing it now?
“One of our clients, Xavier Gaucher, himself a Passive House consultant, is in construction with one of the first Passive houses in Los Angeles, and it’s going up right now in Atwater Village. It is a model project, and I’d like to see it open up to builders and architects during key phases of construction so they can learn it’s not that difficult to achieve.”
The difference between Passive House and conventional construction resides in the details. The Passive House requires a tight construction where there are virtually no gaps in the building envelope. An air-tight barrier is installed to the inside of the insulation (in Southern California’s climate), completely enveloping the structure. Any gaps are filled with caulks, barriers and sealants for draft-free, airtight installation.
Next, an abundance of insulation is provided at walls, roofs, and floors. Detailing of windows, doors and other building components are carefully considered to avoid “thermal bridges,” which allow heat and cold to enter the building. In this way, draftiness is minimized, which keeps the interior at a near constant temperature. This tight, insulated interior space is continually ventilated with fresh, conditioned air to prevent moisture and toxins from building up, which make Passive House buildings some of the most healthy, comfortable structures ever developed.
To certify a Passive House requires completing and satisfying a software package (PHPP) in which every detail of the house is considered: compactness of design, orientation, glazing and door sizes and openings, insulation, solar reflectance of materials, etc. “PHPP is the nuts and bolts, geeky-side of the building standard. But the homeowners don’t have to know about that,” Eve says, “What they need to know is that this will be the most comfortable house they ever lived in. It is living lighter on the earth, and it feels good to know that.”
by Eve Reynolds of Arcolution
Arcolution is one of the very few architectural firms in Los Angeles that is accredited as a Passive House design firm. We have a two story Passive House going up in Atwater Village now. Call us for a consultation! 818-915-2219. Visit www.arcolution.com.
