I have a 1930s semi with a large hip roof. It has purlins on each of the 3 slopes supporting the 4x2 rafters. These purlins are themselves supported by centrally positioned diagonal timber struts to load bearing walls.
I would like to make an "occasional use" hobby room in this loft, and to provide more clear space I would like to remove the purlins and associated struts. To provide the required rafter support my idea would be to insert 100x50 collars fixed between each rafter across the roof space at about 2.4m above loft floor level (The ridge is some 4.2m above the floor). Additional support would be provided by 100x50 timbers from the rafter to the floor at about 1.2m above floor level.
Is this a feasible and structurally sound solution? If so, what form of connection should be used between the rafters and the new timbers?
I would like to make an "occasional use" hobby room in this loft, and to provide more clear space I would like to remove the purlins and associated struts. To provide the required rafter support my idea would be to insert 100x50 collars fixed between each rafter across the roof space at about 2.4m above loft floor level (The ridge is some 4.2m above the floor). Additional support would be provided by 100x50 timbers from the rafter to the floor at about 1.2m above floor level.
Is this a feasible and structurally sound solution? If so, what form of connection should be used between the rafters and the new timbers?