Re: GBlist: cellulose insulation; live roofs; TJIs; stem roofs and foundations,

Mike O'Brien (
Mon, 17 Feb 97 11:43 PST

Hi, Robert--

Well, I worked for three years in a demonstration solar building (TERA I)
that had a live roof and was earth-bermed; in our case the roof was planted
as a grassy meadow. We had a lot of trouble with leaks, despite engineers'
assurances to the contrary about their waterproof system. And fixing the
leaks required excavating the roof to get to the membrane, then puzzling
out where the leak was. It was a hair-puller. So, who is cleverer--water or
designers? Today, I'd have to go with water.

>A live roof is literally having a living environment on your roof (e.g.
>soil and living organisms - plants and things). In general, the
>benefits are that a live roof thrives on sun light and the external
>environment and therefore will have a significantly longer life than
>traditional roofs. The down side is they are extremely heavy. One must
>weight the cost-benefit of the increase in structural elelemts to the
>longevity of the roof. Also, from a "green" perspective one may say
>they are replacing the disturbed eco-system which was displaced by
>building the house with a similar eco-system on the roof.
>While I know the general pros and cons of a living roof. I would like to
>speak with someone who has actual living experience with such an animal.
>Robert Seelig
>Moab, Utah

O'Brien & Associates
Environmental Building Consultants
Portland General Electric Earth Smart program
Earth-Wise Builders

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