I am replacing water damaged floor boards in my bathroom. They were previously tiled and I will be tiling them again. It's an apartment and below the floor is concrete, with joists between the concrete and the boards.
The joists are 45x90mm which I am struggling to find. Is this not a normal size?
Also the joists have a black foam tape on the bottom about 10mm thick which I am also struggling to find.
The joists are not attached to anything and are resting on the floor, held together by the nailed floor boards, which I thought was unusual
The apartment is purpose build and around 10 years old