Fiberglass is one example where polyester resin mixed with glass fiber acts as a reinforcement. Plumbers use a form of reinforced plastic known as PVC when constructing a home plumbing systems. When manufacturing plastic products, special care is necessary. Overheating can cause plastic to become rubbery while underheating will cause plastic to become brittle and easy to break. Even using tight quality control standards in manufacturing, plastic cannot maintain high levels of stress and will fail if used improperly by architects or homebuilders.
Many plastics pose a fire hazard.
While burning, plastic produces vapors, thick smoke, and fuel to a fire. Almost all plastics will burn unless treated with fire retardants. Plastic will burn more fiercely than wood and will produce toxic or corrosive fumes that can easily kill. Unsuspecting homeowners may die well before ignition of a fire takes place and well before the sound of a smoke detector from fumes or smoke from plastic smoldering in their home. Another matter of concern for homeowners when considering plastic ornaments or moldings is ultraviolet radiation.