jacob wrote:

Er, my guess is that the "King Post" and the other timbers joining it
make a truss which supports the roof - the rafters resting on wall
plate and ridge with one or two purlins in between. Where the
horizontal truss timbers overlap they are almost certainly firmly
bolted together.

Yup, sounds likely to me.

So the whole roof+truss are independant of the ceiling joists which

Independant in the sense that the foor structure will not be affected by
what you do to the floor, however related in that the truss structure
also supports the floor.

may be removed however you want. The 2 ceiling joists which cross the
end of the proposed opening would need strengthening as they would
carry the extra load of the ceiling no longer supported by the removed
joists. Perhaps double up with a new timber on top bolted through in
several places.

I think something will need to be done to strengthen the whole area if
much use is going to made of it for storage, since 2 1/2" timber is not
going to be that much for se other than holding itself and the ceiling up.


--
Cheers,

John.

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