The Construction of a Hybrid Home

February 27, 2008 – Vol.12 No. 49

REVIEW: BUILDING WITH AWARENESS, The Construction of a Hybrid Home.

Wouldn’t it be an amazing thing if beginning tomorrow every new home, and perhaps some commercial and industrial buildings too, were built without a conventional energy-hungry central air conditioning system? What if, too, those new buildings generated and stored their own electricity? And what if every step along the way the carbon footprint created by the construction of the new building was considered, and minimized?

The answer? For one thing, new coal-fired powerplants wouldn’t need to be built. Powerplants are built to meet a perceived need in the future, to meet economic growth. If the need isn’t expected to be there, the plants won’t be built.

Writer, director, photographer and editor of Building with Awareness, Ted Owens, sets the stage to ponder, in the DVD and accompanying Guidebook, as to what would happen if we actually put considerable thought into the buildings we construct before one ounce of concrete was poured.

Typically, houses are positioned relative to the nearest roadway - not oriented to take best advantage of free solar energy.

Our houses are generally grossly under-insulated. Home heating technology stems from a time when energy was cheap, thought to be endlessly available, and carbon emissions weren’t a concern. Instead of building an energy-conserving and heat-repelling structure we’ve just been adding more heating and cooling equipment and turning up, or down, the thermostat.

We haven’t taken a look at the natural properties of basic materials that could help keep our homes warm in the winter, cool in the summer. Nor have we given much consideration to the flow of air - cool or warm - in and out of our homes.

We put windows in our homes designed, positioned and sized for aesthetics, for the light they let in, the view we might have, then often cover them up with curtains, shades and blinds.

Generally homes are built based on traditions that go back centuries. There are only minor differences between homes built by the earliest settlers and the ones we now build. Now we’re finding that tradition is not always a good thing.

Building with Awareness is based on the design and construction of a small straw bale solar home built in New Mexico. In extreme detail Owens covers the planning and construction of the home through the positioning of the home on the property and the construction from the slab thermal mass foundation all the way up to the metal roof with photovoltaic panels on top. It’s meant to be a guide to building an energy and carbon footprint aware home, an inspiration to do it, and why we should. The little home is the model, part of the lesson plan.

The success of the home - its ability to offer a comfortable environment year round - is based on a number of different elements: The placement of windows (few on the North side) and roof overhangs to shade summer sun but allow winter sun in; It’s thick - 18 inch R-30 (or so) straw bale in-fill walls along with thick heavily cellulose insulated R-50 roof to keep heat out and warmth in. The adept use of sunlight and insulation work in consort with the home’s concrete slab floor and thermal mass interior walls. All working together, the home doesn’t need central air conditioning even in the hot New Mexico summer. In winter an in-slab radiant heating system is built-in for back-up heating for extended cold periods. (The radiant heating can be connected to a thermal solar system, but isn’t.)

There’s more of course: Local, natural, recycled and low-carbon materials all play a significant role in the home’s construction. Both the DVD and Guidebook go into extreme detail, even including hands-on construction techniques.

Though straw bale construction is not exactly mainstream (though some jurisdictions now include it in building codes) many elements of Building with Awareness would be useful to anyone considering designing and building a custom home using any construction practice or materials. Builders too might take a look to see what could be done differently in a carbon and energy constrained world.

Links:

Building with Awareness
http://www.buildingwithawareness.com

Proven Passive Solar: Low Cost, Low Energy Homes