In article ,
"Zipadee Doodar" writes:
Are the purlins in a pair of semis all in one piece, i.e. continuous through
the party wall? I ask because I think my neighbour has a train set in his
loft, and the slight noise / vibration can be heard in mine. It is not a
problem, just curious!

They aren't in my 1895 house, but they are in contact where they
pass through the party wall, as they both go right through.
However, I doubt the perlins would transmit much noise -- there
are smaller timbers doing the same thing which are fixed to the
tops of the ceiling joists in mine, and I would be more likely
to suspect them.

--
Andrew Gabriel