Greenlake Passive house – post #1

Heliotrope just started this new blog, and we thought it would be a good idea to use it as an opportunity to chronicle our ongoing work toward building one of the first Passive House projects in Seattle.  Of course unless you know something about the Passive House standard this is totally meaningless, so let’s start with that.

Passive House Standard

A Passive House is a very well-insulated, virtually air-tight building that is primarily heated by passive solar gain and by internal gains from people, electrical equipment, etc. Energy losses are minimized, and any remaining heat demand is provided by an extremely small source.  An energy recovery ventilator provides a constant, balanced fresh air supply. The result is an impressive system that not only saves up to 90% of space heating costs, but also provides a uniquely terrific indoor air quality.

Central to this standard is the observation that insulation is cheap (and if using the right kind, friendly to the environment), and it is inherently less wasteful to build a super-efficient envelope than it is to add high-tech gadgetry to a structure in order to reduce its carbon footprint.

The Passive House Standard was developed in Germany and has been in use since 1990.  To date, more than 15,000 housing units and other buildings have been built to the standard, primarily in Germany, Austria and Sweden.  In 2010 it is projected that over 40% of new construction in Austria will be built to the standard, and the EU is working toward implementing it as the future building code for EU countries.  It is new to the US, but interest is growing – and Heliotrope principal Joe Herrin has taken the leap of becoming one of the Northwest’s first certified Passive House consultants.

For more information on the standard, check out these sites:

Passive House US

NY Times article

Wikipedia

Greenlake Passive House

When realized, this house should be one of the most energy efficient buildings in Seattle.  It will utilize the equivalent energy of a standard hair dryer for all heating needs, and it will use 26kBTU per square foot per year for total energy (we’re working on figuring out what the typical house average is for comparison).  It’s a testament to the standard that architects can now, on their own, predict in detail the energy requirements of their buildings.  It has been a very enlightening experience to say the least, and we are very excited about the potential of the standard.

That said, none of it has been – or will be – easy.   Just a few of the challenges we’re facing:

• Build a house 5 times more air-tight than a LEED Platinum/Energy Star home
• Build a home reliant on passive solar heat gain on a site with extremely limited solar exposure (to the south is a 4 story McMansion, only 10 feet away)
• Build a house with twice the insulation and wall-thickness of a standard home, with windows three times better than code, all with a budget target of $200/sf for construction cost

Additionally, we’ve challenged ourselves to accomplish the above without compromising the quality of the design – the spaces, quality of light, character and materiality must be of the standard set by our past “not so efficient but really nice” work.

Oh, and the site for this project is a prominent corner lot on Greenlake Way.  Yep, it’s ON Greenlake.  No pressure or anything, it’s only pretty much everyone we know driving, walking, riding or running by the place on a regular basis.

In future posts we will endeavor to follow the development of the project as it moves from schematic design through the permitting and the passive house review process – then hopefully into construction!  Along the way we’ll pass along some facts and figures interesting to us on the subject of energy use in buildings as well as other issues surrounding sustainability.