Using a structural part of the roof to hang a new floor

[marsaday]

can i hang a new floor off a kingbeam joist sitting in the attic. this triangle structure holds up the roof in the centre.

the 9x2 joist sits on the spine wall of the house and is tied into the frone and back walls. This spine wall is about 65% the length of the house. the final 35% is a span.

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[marsaday]

i do have a SE on the job working some calcs for me, but i just wondered if anyone has come across this sort of thing before.

i think it would be pretty straight forward to uprate the joist using metal plates (flitch) or bolting another joist onto it.

if we can use this joist it makes life a lot easier as we can span the width of the house (3,8m and 4.2m) as opposed to the length which is longer (5.2m and 3.5m).

 

[Deluks]

Ok, answered your own questions there.

 

[marsaday]

i have been told by the SE that i will need to bolt a C beam either side of the joist, add in a timber bearer and then hang joist hangers off this.

does this sound ok? just wanted a few other opinions if possible.

one question though. does this C beam either side need to go into the brick work where the joist does at either end, or is it just bolted to it ?

 

[Deluks]

Sounds good. Remove bricks around the timber to make space for inserting the channel. Then make good afterwards with bits of cut brick and mortar.
You could also bolt the end of the beam to the wall with a heavy duty bracket either side and a couple of M20 bolts through the beam 'sandwich'

Bracket could possibly be made from offcuts of the steel section. Engi will have to advise here though.

 

[marsaday]

yes a brackets sounds a good idea.