Re: [GBlist] low tech green roof?

[David Bergman <bergman@cyberg.com>]

I've asked this question on this forum before, but are any of the green 
roof systems you mention suitable for residential, i.e. wood joisted, flat 
roof structures? I'm still searching for a feasible, affordable green roof 
for our 6-story condo tenement-style building.

David Bergman

John Salmen wrote:
>Hi Alan
>
>Yes I have but with membrane which is readily availabe (Firestone EPDM or
>some equiv.seems to be 'in stock' at most supply houses in my experience and
>quite inexpensive.), however it is difficult to get a roofer to use it for a
>small residential job. I've used Platon foundation drainage as a drainage
>board, I've also used gravel which is pretty low-tech. I would avoid using
>mineral batts for drainage as they could be an additonal source of water
>contamination.
>
>One of the problems with 'green roofs' is the general toxicity of materials
>needed to waterproof quickly takes the shine out of the green in my
>experience and the complexities of waterproofing are anything but low-tech.
>Torch-on and the companion products are pretty offensive materials. Same is
>true to a marginally lesser degree for most EPDM materials and glues.  I
>would prefer to use a polyurethane membrane like Hypalon or keep to that
>family of materials.
>
>And since roofs leak it is useful to look at each component of the system as
>providing some degree of resistance.
>
>On the natural side I have always wanted to try a roof incorporating the
>inverted sod method (traditional icelandic roof). 7 layers of sod
>alternating roots up and down. My thought is that a natural membrane is
>formed in the breakdown of the grass under anaerobic conditions - similar to
>how ponds form.
>
>good luck and keep dry (having just been involved in getting yet another
>flat roof to stop leaking)
>
>John Salmen
>TERRAIN E.D.S.
>
>----- Original Message -----
>From: "Alan Abrams" <awabrams@starpower.net>
>To: <greenbuilding@crest.org>
>Sent: Thursday, November 22, 2001 7:35 AM
>Subject: [GBlist] low tech green roof?
>
>
> > this is a request for *practical* information on
> > detailing a green roof.  Does anyone have first hand
> > experience building green roofs with commonly
> > available, more or less conventional building
> > materials?  I've looked at a few websites on the
> > subject; they seem to require sophisticated membranes
> > and drainage matts--I think it would be beneficial to
> > be able to build with, for example, torch applied
> > modified bitumen and ordinary foundation wall drainage
> > matts.  Low-tech is good, no?
> >
> >
> > Alan Abrams, AIBD
> > 808 Aspen St. NW
> > Washington, DC 20012-2510
> > USA
> > voice and fax 202.726.5894
> > <awabrams@starpower.net>
> >
> >
> > ______________________________________________________________________
> > This greenbuilding dialogue is sponsored by REPP/CREST, creator of
> > Solstice http://www.crest.org, and BuildingGreen, Inc., publisher of
> > Environmental Building News and GreenSpec http://www.BuildingGreen.com
> > ______________________________________________________________________
> >
>
>
>______________________________________________________________________
>This greenbuilding dialogue is sponsored by REPP/CREST, creator of
>Solstice http://www.crest.org, and BuildingGreen, Inc., publisher of
>Environmental Building News and GreenSpec http://www.BuildingGreen.com
>______________________________________________________________________


David Bergman
David Bergman Architect/Fire & Water Lighting + Furniture
bergman@cyberg.com    http://www.cyberg.com
t 212 475 3106    f 212 677 7291


______________________________________________________________________
This greenbuilding dialogue is sponsored by REPP/CREST, creator of
Solstice http://www.crest.org, and BuildingGreen, Inc., publisher of
Environmental Building News and GreenSpec http://www.BuildingGreen.com
______________________________________________________________________