A variety of
problems may occur when applying wood floor finishes, but the source of the problem is often not
the finish itself. Here are of the most common occurrences and some tips on
how to solve the problem. For the consumer, if these problems occur, it can
help you understand the procedures involved in having the problem corrected.
Here's a quick and easy checklist to identify and solve problems
related to wood floor finishes:
ALLIGATORING
This is a condition in which the finish pulls away from itself, causing
ridges in the finish, similar to an alligator's skin. This condition can
occur in both water-based and oil-modified finishes. There are many possible
causes, including poor wetting of the finish, contamination of the finish,
application under cold temperatures, application of a new coat before the
previous coat has dried, application of a heavier coat than is recommended,
or the use of thinners that cause the finish to dry too quickly. The
solution is to screen and recoat after the finish has dried sufficiently.
APPLICATION STREAKS
This condition is usually associated with water-based finishes. It often
occurs when an improper spread rate is used - too much or too little finish
is applied - or if the finish is not applied evenly. Excessive air movement
and abnormally high temperatures can also be responsible for causing the
finish to dry too quickly, so that a wet edge of finish is pulled over one
that has already dried. The problem can also be caused by applying a satin
or semi-gloss finish that has not been stirred properly. The solution is to
screen and recoat after the finish has dried sufficiently.
BLEED-BACK
This condition, associated with stain application, occurs when excess stain
seeps from the grain or from the spaces between boards. The most obvious
cause is excessive stain application, but low-viscosity stain may also be
the culprit. The solution is to wipe off the excess stain and let it dry
thoroughly before applying another coat. If finish has already been applied
over bleed-back, a complete resand is required.
DISCOLORATION
Some finishes are amber in appearance and will yellow even further over
time. Wood lying in direct sunlight will fade over time. These are natural
changes - the former condition cannot be prevented, despite the pervasive
myth that an oil-modified finish recoated with water-based finish will stop
ambering. The latter condition can be prevented by shading the light source.
Erratic discoloration can also occur - especially in white oak - if a good
sealer is not used. This is called tannin pull.
EXCESSIVE AND EARLY WEAR
Often, the cause is improper maintenance procedures that have either failed
to fully remove grit from the floor's surface, or the introduction of water
or strong cleaners. Dog nails, high heels and chair legs also contribute to
the problem. Make sure the customer understands proper maintenance
procedures, including regular dust-mopping with an approved wood-floor
cleaner. (Some cleaners may leave a residue that will prevent good adhesion
on a recoat.) If recoating is necessary, the owner should pay for it.
ORANGE PEEL
If the surface of the finish has a texture that resembles an or- orange
peel, the problem may have been caused by rolling a finish, which then dries
too quickly. When that happens, the texture is "frozen" into place
before the finish has a chance to flow out and level. The solution is to
screen and re-coat.
PEELING, BUBBLES, BLISTERS AND
FISH-EYES
Any of these conditions can mean that the floor was not sufficiently
screened between coats of finish, or that soap or some other contaminant
substance was not removed before coating. It's also possible that the
affected coat is incompatible with the finish or stain previously applied,
or a contaminated applicator may be responsible. Problems in the top-most
finish coat can be screened and re-coated, although severe problems may
require complete sanding and refinishing.
ROUGHNESS
The cause is often contamination of the finish during dry time, although
moisture beneath the floor can also cause the wood grain to rise. If a
moisture problem is evident, this must be corrected before re-screening and
re-coating.
STAINS
Spilled water and other liquids, including the residue from incompatible
cleaners, can stain finish. Cloudy surface finish can be fixed by lightly
rubbing with a proper cleaner and buffing, although some stains require
screening and recoating. Strong chemicals should not be used to remove
stains.
STICKY BOARD SYNDROME
This occurs when excessive tannic acid in the wood prevents the finish from
adhering to the wood. This is most common with oil modified finishes and
with white oak. When one board or several boards scattered throughout the
floor will not take stain or finish, the only solution is to repair the
floor by replacing the boards.
UNEVEN GLOSS OR SHEEN LEVELS
Insufficient stirring of finish prior to application, a contaminated finish
applicator and uneven sanding or finish thickness are typical culprits. All
require rescreening an re-coating. Great care should be take if using
different sheen levels. Sometimes, multiple coats of satin, three or more
coats will start to give a hazing look to the finish coat.
See Related Pages:
~Types of Wood
Floor Finishes
~Finishing Wood Floors
~Mixing
Finishes on Wood Floors Oil over Latex and VS
~Technical
Questions & Answers - FAQ's
