We are weighing up our options for the GF "slab" as we prepare for the start of our extension.
I have attached the plan below. The existing rear patio which sits where the extension will go is about 400-500mm below the FFL of the existing house. Assuming the patio is to be removed or partly removed this level difference will be more like 700mm+, a large void to fill with a traditional slab?
I was talking to friends at the weekend who have used beam and block for their extension and until then i had never given it a thought but am now wondering if this would be a better option? Could the patio be left there with some oversite concrete to ensure nothing ever grows down there then the B&B floor sits above this giving a lovely ventilated void. I could then run the services underneath before screeding/UFH.
I have seen some negative opinions on B&B so was after some expert advise.
I have attached the plan below. The existing rear patio which sits where the extension will go is about 400-500mm below the FFL of the existing house. Assuming the patio is to be removed or partly removed this level difference will be more like 700mm+, a large void to fill with a traditional slab?
I was talking to friends at the weekend who have used beam and block for their extension and until then i had never given it a thought but am now wondering if this would be a better option? Could the patio be left there with some oversite concrete to ensure nothing ever grows down there then the B&B floor sits above this giving a lovely ventilated void. I could then run the services underneath before screeding/UFH.
I have seen some negative opinions on B&B so was after some expert advise.
