Building on garage slab

[b21playa]

Hi all

I'm adding a downstairs w/c and the only space I can fit this is at the foot of the stairs by taking space out of one of the garages. There is a height difference of about 450mm. What would be the best way to do this; brick/block outer and infil with concrete laid on a dpm or a wooden subfloor?

Thanks in advance

 

[23vc]

You don’t know the garage slab will take the weight of masonary walls, so you may be best with properly insulated studwork and insulated floor whether timber or concrete. Are you building regging it?

 

[b21playa]

Thanks for the reply. Wasn’t thinking of full masonary walls, just to contain insulated concrete for the floor.

yes this is going in full plans which are currently being drawn up for work to most of the house.

wanted to start thinking of how to tackle it as it will be one of the first jobs, so that we can rip out 1st floor bathroom while changes are being made