Probuild Specifications If you are an Approved Applicator or Distributor please login here before continuing. What type of substrate are you painting Ceiling L4 finish Ceiling L4.5 finish Ceiling L5 finish Exterior new concrete or plaster Exterior preprimed weatherboard Interior doors and trim Silver system Probuild interior exterior doors and trim Platinum system Probuild interior Low Sheen L4 Probuild Interior Low Sheen L5 Probuild interior walls and ceilings enamel finish wet service areas