Our bath has been fitted without the rim sitting on a ledger board/baton, is this important?

Hi Pete

The answer depends on the manufacturer of the tub. All cast iron tubs and most acrylic and fiberglass tubs require the ledger board, BUT some manufacturers use a CLIP system that do not require the ledger board. I would get the name of the tub and the manufacturer and look online for installation instructions. If the board is required on your tub then it MUST be installed somehow!

Mark