Household
Hazards
Algae:
Microorganisms that may grow to colonies in damp environments,
including certain rooftops. They can discolor shingles. Often
described as "fungus."
Alligatoring: A
condition of paint or aged asphalt brought about by the loss
of volatile oils and the oxidation caused by solar radiation.
Causes a coarse checking pattern characterized by a slipping
of the new paint coating over the old coating to the extent
that the old coating can be seen through the fissures.
"Alligatoring" produces a pattern of cracks resembling an
alligator hide and is ultimately the result of the limited
tolerance of paint or asphalt to thermal expansion or
contraction.
Asbestos: A
common form of magnesium silicate which was used in various
construction products due to its stability and resistance to
fire. Asbestos exposure (caused by inhaling loose asbestos
fibers) is associated with various forms of lung disease. The
name given to certain inorganic minerals when they occur in
fibrous form. Though fire-resistant, its extremely fine fibers
are easily inhaled, and exposure to them over a period of
years has been linked to cancers of the lung or lung-cavity
lining and to asbestosis a severe lung impairment. A naturally
occurring mineral fiber sometimes found in older homes. It is
hazardous to your health when a possibility exists of exposure
to inhalable fibers. Homeowners should be alert for friable
(readily crumbled, brittle) asbestos and always seek
professional advice in dealing with it.
Bleeding: The
migration of a liquid to the surface of a component or
into/onto an adjacent material.
Blister: An
enclosed raised spot evident on the surface of a building.
They are mainly caused by the expansion of trapped air, water
vapor, moisture or other gases.
Blue
Stain: A
bluish or grayish discoloration of the sapwood caused the
growth of certain mold like fungi on the surface and in the
interior of a piece, made possible by the same conditions that
favor the growth of other fungi.
Bubbling: In
glazing, open or closed pockets in a sealant caused by
release, production or expansion of gasses.
Buckling: The
bending of a building material as a result of wear and tear or
contact with a substance such as water.
Carbon Monoxide: CO.
A colorless, odorless, highly poisonous gas formed by the
incomplete combustion of carbon.
Cohesive Failure:
Internal splitting of a compound resulting from over-stressing
of the compound
Condensation:
Water condensing on walls, ceiling and pipes. Normal in areas
of high humidity, usually controlled by ventilation or a
dehumidifier
Corrosion: The
deterioration of metal by chemical or electrochemical reaction
resulting from exposure to weathering, moisture, chemicals or
other agents or media
Crater: Pit
in the surface of concrete resulting from cracking of the
mortar due to expansive forces associated with a particle of
unsound aggregate or a contaminating material, such as wood or
glass.
Crazing: A
series of hairline cracks in the surface of weathered
materials, having a web-like appearance. Also, hairline cracks
in pre-finished metals caused by bending or forming (see Brake
Metal).
Cupping: A
type of warping that causes boards to curl up at their
edges.
Dampproofing: A
process used on concrete, masonry or stone surfaces to repel
water, the main purpose of which is to prevent the coated
surface from absorbing rain water while still permitting
moisture vapor to escape from the structure. (Moisture vapor
readily penetrates coatings of this type.) "Dampproofing"
generally applies to surfaces above grade; "waterproofing"
generally applies to surfaces below grade.
Decay:
Disintegration of wood or other substance through the action
of fungi.
Distortion:
Alteration of viewed images caused by variations in glass
flatness or in homogeneous portions within the glass. An
inherent characteristic of heat-treated glass.
Drippage:
Bitumen material that drips through roof deck joints, or over
the edge of a roof deck.
Dry
Rot: See
Fungal Wood Rot.
Feathering Strips:
Tapered wood filler strips placed along the butt edges of old
wood shingles to create a level surface when re-roofing over
existing wood shingle roofs. Also called
"horsefeathers."
Fungal Wood Rot: A
common wood destroying organism which develops when wood
containing material is exposed to moisture and poor air
circulation for a long (6 months +) period of time. Often and
incorrectly referred to as dry rot.
Fungi
(Wood):
Microscopic plants that live in damp wood and cause mold,
stain, and decay.
Incompatibility:
Descriptive of two or more materials which are not suitable to
be used together.
Lead
Based Paint: Lead
is a highly toxic metal that was used for many years in
products found in and around our homes. Lead may cause a range
of health effects, from behavioral problems and learning
disabilities, to seizures and death. Children 6 years old and
under are most at risk, because their bodies are growing
quickly.
Migration:
Spreading or creeping of a constituent of a compound onto/into
adjacent surfaces. See bleeding.
Mud
Cracks:
Cracks developing from the normal shrinkage of an emulsion
coating when applied too heavily.
Mushroom: An
unacceptable occurrence when the top of a caisson concrete
pier spreads out and hardens to become wider than the
foundation wall thickness.
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.
