[Cob] Weatherproofing a cob bench

[yewberry at wavecable.com]

Terra Incognita wrote:

>I've seen uncovered cob benches elsewhere. 

Where?  And do you know if they held up long-term?

>Is a lime plaster my best bet or 
>are there other options?

Lime is water permeable if water is left to sit on it (in 
the case of a horizontal surface, like a bench seat).  I 
can't think of any natural, waterproof coating that will 
hold up to the elements for more than a season in most of 
the Continental U.S.  You might have luck with a 
beeswax/linseed combo, but I'm guessing you'll have to 
renew the finish every year.

Cob simply doesn't perform well without a roof.  Any 
chance you could build one into the bench (instead of 
making it free-standing)?  That's what we did with ours, 
and it's holding up well:

http://home.wavecable.com/~yewberry/cobbers/back8-4-06.jpg

Brina