- Q.The new water-based
urethane finishes are easier to apply than the old
solvent-based polyurethanes. But are they as
A.Painter Dan Greenough, a
member of PaintCraft Associates, a San Francisco
Bay-area guild of professional finishers,
responds: I have found that with most
water-based varnishes, an extra coat is required
for adequate coverage and protection of the
surface. According to Flecto, a manufacturer of
varnishes (800/635-3286), their water-based
Varathane Diamond Finish is "very close" in
hardness to their oil-based Liquid Plastic Interior
Wood Finish. Experience and logic tell me that most
water-based clear finishes are not quite as hard as
their conventional oil-based equivalents.
Water-based finishes have some definite
advantages. Because they have relatively little
odor, they are appropriate for use in occupied
homes where the clients are sensitive to odors.
Water-based finishes dry quickly, allowing several
coats to be applied in one day. They also dry
clear, without the yellowing associated with
These advantages also point to some potential
disadvantages. Fast drying sometimes results in
more prominent brush strokes. Some clients prefer
the amber color of oil-based polyurethanes.
Finally, water-based clear finishes always raise
the grain of the wood. This increases the sanding
time, which is an additional cost.