Cohousing-L Mailing List: Re: Re: heating ideas

[tom ponessa (tom_ponessa]

Re: Graham Meltzer's reply to Heating ideas

These are also known as masonry heaters or Russian heaters.
There are commercial models (Tempcast, Envirotech etc see ads
in Fine Homebuilding) as well as  those built by masons. Tempcast
starts at about $3000 or so (U.S. which means $7,834,000 Canadian).
This doesn't include the exterior masonry finish (required).There have
been articles inFine Homebuilding about custom made
models (Dec '91, Aug '92).

They burn the wood then burn the gasses in a secondary combustion
chamber above the wood.  Then the hot residue is routed up and
down a few times before going up the chimney. This activity extracts
the heat which is held in the masonry (or soapstone in one case).
Tempcast claims better than 90% efficiency and particulate
emmission of less than 1 gram/hour in some cases. These things
can also burn softwood and produce negligable creosote. So if
you find discarded wood pallets your heat is free.

However I have reservations about the warehouse. If you have one
heater and people have there own rooms, doors need to be left
open for the heat to radiate in. By its nature it must be centrally
located in the building. It is heavy and the floor may need reinfocing.
The roof will have to be pierced for the chimney. Codes may
require an external air supply (there could be backdrafting and
pollution of the interior space without it). I wouldn't construct a
firebox with anything other than new firebrick and code may
require it. Finally, I suspect the cost will be not so cheap and
if it is custom you MUST find someone who knows how to do it.
Someone with references and a track record. The potential for
disaster is too great otherwise.

I think masonry heaters are the best solution ecologically
and in terms of energy efficiency (after 100% solar).
I plan to have one in my house if and when I build it. I think they
are ideal for a new project. For a retrofit it may not be so simple
to recommend.. The number and type of windows is a big factor-
are they single or double glazed? If Jerry Jameson can give us some
more detail about the living arrangements and the building it
would help