In article ,
r.p.mcmurphy wrote:
hey up! i have a workshop to which i have fitted a car lift...but i now
need to remove the ceiling ties(to which there never was a ceiling
fitted), and the purlins which are half way up the 45degree rafters, in
order to be able to lift the car into the roof space suficently enough
to allow standing room underneath. i know the only way is to
suficently strengthen the rafters so that they dont sag and install
collars higher up. but i want them as high as possible..not just the
third of the way up that is recomended. so my thinking is to strenthen
the rafters with u chanel 3 or 4 mm steel cupping and screwed or bolted
to the raters. then using steel strips as the collars but higher
up...say in the top third. has any one any experience of this method
or any comments? all very welcome! (arcitect due to advise later next
week..but would like some feedback on my ideas)

I had similar in my attic conversion, and the existing purlin was replaced
by two steels - postions determined by the size of the exposed sloping
ceiling. Obviously, calculations were done to support this. They are tied
to the rafters.

I'm surprised you're so tight for space that a purlin position matters? In
my case, it was for cosmetic reasons.

--
*Isn't it a bit unnerving that doctors call what they do "practice?"

Dave Plowman London SW
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