Litigation and repair work
involving failed fire-retardant
treated (FRT) plywood
is still in full
swing. According
to some experts,
however, the
same chemical
process that
ruined the plywood
is causing a
slower but more
dangerous problem:
the degradation
of roof
structural systems
built with FRT
framing lumber.
FRT plywood
failures can take
from two to ten or more
years to develop. Problems
with the plywood have been
seen in thousands of condos
and townhouses, where the
plywood was used on roofs to
prevent fires from
spreading from
unit to unit.
Over the years,
gradual degradation
had
caused plywood
on these roofs
to sag and
crumble. Workers
have even
been known to
fall right
through FRT
plywood roof
sheathing. Fortunately,
few
residential units have any
FRT wood in their framing.
Many commercial buildings,
on the other hand,
have trusses or rafter systems
made of FRT dimensional
lumber. Now the owners