"SteveB" wrote on 19 May 2005:

Like horizontal cripples. The short boards that go inbetween
studs. Where there is a cripple, if you make a hole above it,
the insulation only fills only down to where the cripple is,
then you have a hollow space.

Not to be picky, Steve, but there is no such thing as a horizontal
cripple. A cripple stud is a vertical that goes between the window
or door header and the top plate (upper cripple) or bottom plate
and the window sill (lower cripple).

What you correctly describe as being a problem for insulating is
called "fire blocking" or "nogging."

--
Doug Boulter

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