Old slab and new construction

[kherrmann]

Hello,

I want to put a prefab structure on an existing slab. I understand that the structure can be no bigger than the slab, but is there a problem if the structure is smaller than the slab?

Thanks

 

[budro]

what kind of structure are you talking about? is this structure a small metal buiding or an addition to an existing house? water will be a problem if it runs off the structure onto the slab which will then run under and into your structure unless you address this and stop it. budro