S
smoothound
just wondering why remove the original boards unless they are in bad nick? - they may be less than 18mm - just lift em - add extra noggins and check the joists are well bedded - screw the floor boards back down tight - fit the cement boards (hardi) using a thinish layer of flexible adhesive to fill gaps from board cupping etc - (some say non-flexible is OK but I prefer felxible under the hardiboards) - and use the proper anti-corrode screws - and go from there