[Greenbuilding] Oak

[Chris Green]

Lawrence Lile wrote:
> A guy was asking me offlist about using oak for beams cut onsite in
> houses.  I seem to remember something on the list about problems with
> beetles eating up the wood. 
In some places oak will be attacked by a critter called the "powderpost 
beetle." One building I read about at Oxford University--be building was 
at the University, not me, unfortunately--was discovered to have post 
powder beetles in the 16" x 16" beams.
Four hundred years after the hall was built.
When they built the hall, the university's foresters also planted a 
small forest of trees on university-owned land in order to have timbers 
to replace the beams. Talk about preplanning....
>  What about those oak log homes that
> Gastineau and others make? Is this a real problem, and how is it dealt
> with?  Is it a regional problem? Or just a wrongheaded code official
> causing trouble?
>   
A lot of old traditional timber framed buildings in England and the 
eastern parts of North America have oak timbers. Perhaps the official 
should get a library card and study up on these, or -- better yet-- take 
a timber framing workshop at some place like the Fox Maple School of 
Traditional Building (link at end)
> I know of houses built 100+ years ago with rough sawn oak framing, they
> are the only ones still standing, despite having foundations that are
> just rocks set on the ground.  The pine-framed houses from the era all
> died of termites already.  
>   
You pretty much answered your own question there: Treating the timbers 
with a boron preservative, and perhaps a lime wash, would probably 
extend the life of the framing members quite a bit.
Especially if they don't get wet enough for the borax to leach out.

Another traditional finish is to paint the wood with linseed oil mixed 
with ocher, or iron oxide pigments. These are the basic ingredients to 
make Falun Red paint, or "barn paint." It seems to help preserve the 
wood a bit.
The Falun red oxide pigment comes from  the Falun mine in Sweden, (or 
came from--I don't know if they're still operating this mine, which 
started back about 250 years ago) but locally obtained ocher supplies 
can be used if you can find a deposit near by.

By this you can conclude that I don't think beetles are that much of a 
problem, and the risks can be dealt with beforehand.

Your contact is darned lucky to have this prime material on site. I say 
go for it!
Just remind him to plant replacement trees so repairs can be made....4- 
or 500 years from now. :-)

You might also suggest that they use an Open Plan concept so that the 
building's interior can easily be changed when the needs of the 
occupants change over the years. Tedd Benson is one of the leading 
proponents of this concept.

Wiki timberframe article:
http://en.wikipedia.org/wiki/Timber_framing

Tedd Benson's home page:
http://www.bensonwood.com/

Fox Maple School (and Joiners' Quarterly link.):
http://www.foxmaple.com/index.html

Cheers,

Chris Green.