building on ledge.

[simple_gifts]

I'm thinking of getting a garage or outbuilding built from http://www.miracletruss.com/ these guys. I kind of like the idea of using steel, not interested in reroofing, painting etc...

My backyard is sort of small (1/3 acre lot), it is exposed bedrock in some places (ground level) to maybe 1 - 2 ft of top soil. Can this be built on? The bedrock is most likey granite gneiss, not garbage like shale or brownstone. I'm thinking of piers but would also like a concrete floor. Can concrete be poured directly on bedrock? Can the piers be tied directly to bedrock? I don't have the mandatory 4' or so of depth for a foundation or "standard" piers.

I'll probably call a civil engineer, but I'd like some feedback so I can ask the right questions, find out whether he "knows his stuff" etc. I want to know if he doesn't know.... I'm open to other ideas too...

editrimarily interested in reponses from northern climate oriented people. Slab on dirt doesn't really cut it in New England.

Any feedback appreciated.

-Thomas

 

[Auto-Union]

Slab on bedrock should work. Make it 6" with some control joints.

 

[Bret Chase]

we pour on ledge all the time. it's much less of an issue with a residential property than a commercial one.

 

[Lonnie]

The open floor idea would make a great residense with lofts and hugh open areas. I wonder how much work siding and insulation would be to make it look like a home and easy to heat and cool.