Hi - I'm hoping to remove 3 neighbouring ceiling joists (one's already been cut and noggined for an attic hatch) next to an internal solum-to-ridgeline brick wall. The joistless span would be 150cm. Joists are 15cm, span 380cm, roof is single pitch with simple rafters plus ceiling joist and ridge board. Ridgeline clearance above the joists is a bit over 120cm. Roof tiles are cement; walls stone.
To prevent spreading while keeping the work feasible I wondered about a section of roof beam under the ridge board, slotted into the tip of the brick wall at one end and fixed to 2-3 of the next rafters at the other side. I was hoping it might be enough to fix this with metal hangers at the tops of the rafters or support it on substantial collar ties - but maybe I'd need to double up the joists and rafters, and / or maybe trusses?
I did also wonder if tying the rafters to short purlins at the joist/rafter intersections, fixed to the rafters and joists on either side of the intended gap might do the job.
Or doubled-up noggins spanning the entire gap - but I imagine this wouldn't be strong enough: on one side I could screw ply to either side of the joists and noggin to form a rigid box structure extending 60cm inwards from the wall, but on the other side this could be only around 20cm deep and would need big holes in it for a duct and soil pipe.
Any advice much appreciated! Thanks for looking
To prevent spreading while keeping the work feasible I wondered about a section of roof beam under the ridge board, slotted into the tip of the brick wall at one end and fixed to 2-3 of the next rafters at the other side. I was hoping it might be enough to fix this with metal hangers at the tops of the rafters or support it on substantial collar ties - but maybe I'd need to double up the joists and rafters, and / or maybe trusses?
I did also wonder if tying the rafters to short purlins at the joist/rafter intersections, fixed to the rafters and joists on either side of the intended gap might do the job.
Or doubled-up noggins spanning the entire gap - but I imagine this wouldn't be strong enough: on one side I could screw ply to either side of the joists and noggin to form a rigid box structure extending 60cm inwards from the wall, but on the other side this could be only around 20cm deep and would need big holes in it for a duct and soil pipe.
Any advice much appreciated! Thanks for looking
