I know that hardie backer board is preferred for plasterboard installation - I have a stud wall that has fallen off and the plasterboard has all crumbled so I will need to get that replaced - I thought about screwing in some hardie board after I have removed the old plasterboard but I wanted to know whether I could then paint it (or even leave it plain) until a few weeks time when I can get a tiler in - The shower is constantly used so thats important to bear in mind !!