Done right, exterior trim can last a long
time. I've seen 17th and 18th century
homes in New England whose original
moldings — everything from cornices to
watertables — were still solid after centuries of exposure
to the elements. But done wrong, exterior trim
will be one of the first parts of a house to go. While
working on contemporary homes on the West Coast,
I've encountered 10-year-old window casings and
porch railings that needed repair or total replacement.
Why do some trim jobs last while others don't?
Unfortunately, there's no simple answer or single solution.
Instead, I've found it best to pursue a combination
of strategies. These include using rot-resistant
woods and designing