hi
i have been digging out for my conservatory foundations but after digging down almost 1 metre i have yet to hit solid ground also i have not reached the foundations on my house ,my house was built about 3 years ago ,from damp proof there is 8 bricks and so far 2 course of foundation blocks, most of the ground i have been digging is broken brick or sand stone mixed,will i have to have piled foundations or would i be ok to put it on a raft,any body get any ideas?

help!
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You have what i think is sometimes referred to as "made up" ground. Even after 3 years it will still be "settling" and it would be advisable to go down to house foundation levels. Seems a bit of over kill to go for "piling" unless the house has got that.

Your conservatory is most likely outside the scope of building regs but if it was applicable most Council building control departments have a policy whereby extensions to properties which have a 'designed' foundation i.e. pad, raft or piled should be provided with the same type of foundation. This is to combat the problem of differential settlement where one part of a building subsides or settles at a different rate to that of other parts of the same building, which could lead to cracking and possible structural failure.

I'm not recommending this but I have seen some conservatory base builders add steel mesh reinforcement to the foundations when the ground is "made up" - it seems to have worked.

You can see a step by step guide to base building at
http://www.conservatoriesonline.com/construct1.htm