Polypropylene Fiber is a reinforcing fiber that is quick and easy to use. Simply sprinkle it into the mortar and mix for a few minutes to distribute the fibers. Polypropylene fiber and animal hair gives plaster lateral strength.
For base coat of plaster (NHL 2.0 or Lime Putty Stucco/Plaster Basecoat) you will need approx 3 oz (three tightly packed cups) of Polypropylene Fiber per five gallon bucket of plaster. Actual amount needed will vary depending on installation techniques.