Lath and plaster are fire resistant and are usually used in ceilings to prevent fire spread. In the case of fire, the longer the plastered ceiling remains in place, the greater the fire will be prevented to spread between floor levels.

What is the fire rating for plaster walls?

Gypsum-based plaster at 5/8-inch is sufficient to produce a one-hour fire-rated wall.

How do you make plaster heat resistant?

Any minor cracks can be repaired using VITCAS® HEAT RESISTANT FILLER. It is possible to re-coat the material with PVA and reskim after the plaster has dried if a second coat is necessary for any reason. When dry the finished surface forms a very hard heat resistant surface that can be painted over as required.