Fitting instructions say it's necessary to fit a heat resistant board below the base of the hob when installing above a draw/cupboard. Is this absolutely necessary and as a aboard wasn't supplied with the hob, any idea where this board can be bought? Also any idea of the thickness as there is very little clearance!
If the instructions say it's necessary then that is what you have to do.
If there's nothing in the instructions about the thickness - contact the manufacturer. Or return and buy a gas hob that does not need the heat resistant plate below - as I've never came across a hob that need this. The heat shields is normally incorporated in the hob itself.