Household Hazards (continued)

Photo-Oxidation: Oxidation caused by rays of the sun.

Ponding: A condition where water stands on a roof for prolonged periods due to poor drainage and/or deflection of the deck.

Pop-Out: See Stucco Pop-Out.

Radon: A naturally-occurring, radioactive gas which is heavier than air and is common in many parts of the country. Radon gas exposure is associated with lung cancer. Mitigation measures may involve crawl space and basement venting and various forms of vapor barriers.

Scrap Out: The removal of all drywall material and debris after the home is "hung out" (installed) with drywall.

Seasoning: Removing moisture from green wood in order to improve its serviceability.

Settlement: Shifts in a structure, usually caused by freeze-thaw cycles underground.

Sludge: Term for the waste material found in sump pump pits, septic systems and gutters.

Spalling: The chipping or flaking of concrete, bricks, or other masonry where improper drainage or venting and freeze/thaw cycling exists.

Splitting: The formation of long cracks completely through a membrane. Splits are frequently associated with lack of allowance for expansion stresses. They can also be a result of deck deflection or change in deck direction.

Ultraviolet Degradation: A reduction in certain performance limits caused by exposure to ultraviolet light.

UV Rays: Ultraviolet rays from the sun.

Veining: In roofing, the characteristic lines or "stretch marks" which develop during the aging process of soft bitumens.

Warping: Any distortion in a material.

Water Vapor: Moisture existing as a gas in air.