Another paint innovation of the early 19th century was the
use of flatter oil paints achieved by adding more turpentine
to the oil, which thus both thinned and flatted them. By the
1830s the velvety look of flat paint was popular.
Wherever decorative plaster was present, as it frequently
was during the height of the Federal period, distemper paints
were the coating of choice. Being both thin and readily removable
with hot water, they permitted the delicate plaster moldings
and elaborate floral or botanical elements to be protected
and tinted but not obscured by the buildup of many paint layers.
(The use of water-based paints on ceilings continued through
the Victorian years for the same reasons.)
Unfortunately, flat paints attract dirt, which is less likely
to adhere to high gloss surfaces, and are thus harder to wash.
Victorians tended to use high gloss clear (or tinted) finishes
such as varnish or shellac on much of their wood trim and
to use flat or oil paints on walls and ceilings.