'Leapfrog' houses: a non-architect's LEED Platinum adventure

Charlie Weiss isn't an architect. Nor is he the football coach at Notre Dame (that would be Charlie Weis, with one 's'.) But the two houses he's seen constructed in southwest Portland off Terwilliger Boulevard are some of the greenest yet to be built in Portland.

Weiss, who studied environmental design in the 1970s and is now a partner in a market research company, worked with Lake Oswego architect Kathy Kramer and local builder Green Hammer Construction to create two 1,600 square foot houses that are poised to earn 105 LEED points apiece - good for a top 'Platinum' rating and then some.

The roof is a result of studies at the University of South Florida that Weiss found. It's made of zinc-aluminum alloy to reflect radiant energy. And because there are no penetrations of the surface from a chimney or otherwise, it has a very high R-56 thermal value.

There is also a 6,000-gallon rainwater storage tank installed underground. The rainwater is filtered and used for showers as well as flushing toilets. Unless there's a major summer drought, Weiss says they can live almost entirely on rainwater. Hot water come from a ground source heat pump.

The walls are 8 inches thick, providing excellent insulation (an R-32 thermal rating) and preventing what's called "thermal bridging", in which heat or cold is conducted through the wood structure. There are also fiberglass window frames that help keep air out.

The house is so air-tight, in fact, that when it was measured by Earth Advantage, it was the highest ever tested by that organization. Weiss had to have fans installed around the house to discharge air.

Radiant heating is embedded in concrete floors, which are made from 45 percent recycled fly ash, and the wood stairway treads were milled from a fir tree on site. Tall ceilings make the houses' small floor plates seem larger. Weiss cites houses he saw for staff at Yellowstone National Park as inspiration.

Weiss and his family are living in one of the Leapfrog houses, but the other is for sale. And with temperatures today predicted to be in the mid-90s, I can tell you it was also very hot when I visited the Weiss house last week, at least on the outside. But inside you'd have thought it was November.

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