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Bricklaying
Concrete mix rather than wall ties?
I read and seen details which shows a 'concrete mix' within the cavity of a cavity wall at foundation level (below ground), its supposedly meant to prevent the cavity from collapsing, my question is rather than filling the cavity with concrete mix below ground, can you not use wall ties to tie the foundation wall together instead? Do you have to use the concrete mix instead?
4 Answers from MyBuilder Bricklayers
Best Answer
A concrete mix below ground level doesn’t actually serve the purpose of keeping the inside and external brickwork tied together. It’s more for the purpose of preventing the external course collapsing when you’re bringing external areas up to finish floor height - hope this helps
Answered 26th Apr 2022
You use both but he is correct you use a weak mix of semi dry conrete
To fill the cavity up 2 /3 courses below Dpc height sloping out wards so any excess water condensation is sent out through external brickwork
Answered 3rd Apr 2022
You have to use the concrete mix for cavity fill.No otherway around it
Kind Regards Alec
Answered 6th Apr 2022
Concrete in the area below damp up to 6” is a regulation requirement and it acts as a further strength from the foundation of concrete to support your build above finish floor level,wall ties are generally used only fro dpc up unless the amount of block work to dpc is more than 2 courses of blocks,and then obviously more concrete infill is required to take the finish of the concrete to 6” below dpc,hope this helps
Answered 13th Apr 2022
