The following lines were added (+) and removed (-):
Hollow core:Hollow core: Hollow-core doors are made from two thin veneer plywood or hardboard faces. Between the two are supports, often made of cardboard, to help keep the door rigid. These doors are light, inexpensive, prone to puncture, and ineffective as sound barriers.Solid core:Solid core: Some manufacturers carry solid core doors made from high-density fiberboard or hardboard. A top-quality engineered-core door may be constructed with hardwood sticking.