A.Michael Purser, a
second-generation wood-flooring contractor in
Atlanta, responds: While it's true that floor
finishes with UV inhibitors and stains with
pigments (as opposed to dyes) will slow down color
degradation in both the finish itself and the
underlying wood, manufacturers of these products
don't claim to be able to stop the problem. And UV
light (from the sun and from other sources) isn't
the only cause of fading and discoloration; heat
and moisture can also be factors. To slow down
— notice I didn't say "prevent" —
fading and deterioration, you'll have to manage all
three causes. The key is to avoid extremes of
exposure to sunlight and humidity.
If you are building a new house or adding on and
have any input in the selection of new windows, you
would be wise to consider low-E glass. Made of
transparent metallic oxides, low-E coatings can
reflect up to 90 percent of long-wave IR light, the
kind that creates the heat that accelerates
oxidation in wood. But low-E glass doesn't stop a
lot of UV light, the most damaging type. For that,
you'll need to choose windows that feature glass
with a UV-blocking coating. If you have to work
with older existing windows, you might want to
investigate window films. Often applied to the
interior glass of historic properties —
where protecting wood floors, old rugs, and
expensive fabrics is a high priority —
these thin, multilayered film products have various
coatings that can selectively reduce UV, IR, and
visible light, all of which contribute to
fading.
Finally, there's a low-tech solution: window
coverings. Drapes, shutters, and blinds may not be
what you had in mind when you bought or built your
home, but this is an approach previous generations
put to good use. Compared with refinishing your
floor or retrofitting new windows, window coverings
are also fairly cheap. The bottom line is that
sunlight is very destructive to wood, as well as to
the various finishes used to protect it; you can
slow fading down, but you can't stop it. So your
focus should be on the light entering the room and
how to reduce its intensity.