How to support existing rafters with a new ridge beam?

[frslam]

Morning. Sounds interesting.

What's the span you are dealing with?

As for hardware have you had a look through the Simpson website?

Update! Gable and mid-house load bearing partitions built, gable panel bolted by 10 x 150 concrete bolts top and bottom of each panel stud, 45 x 45 strapping fitted to block wall with 50mm PIR in between block wall and load bearing wall. Rafters have been extended (deeper) with 45x95 C24, glue and screw @ 600 centres, 45x95 C24 mini collars fitted to sit directly above the beam - 115mm beam thickness so tried to get the collar seat the same so the rafter edges and the collars both sit on the beam. Old rafter/ceiling ties cut away with timber triangles glued and nailed between remainder of ceiling ties and the rafters before fitting 18mm ply gussets on each side of the rafters. Top of beam approx 6m from sublfloor level. Still to fit high wind ties from rafters to ridge beam, wall plate hold down straps, tie down twist straps from the rafters to the walls and gable straps from the panel through first 2 rafter pairs (that'll have to wait until the roof is being redone in slate because I'll have to remove the odd sarking board here or there to fit the straps

 

[frslam]

With regards to birdsmouth cuts, yes, usually one third of material can be removed.
On the roofs I've see with 45x95 timbers, they are plumb cuts, never seen a birds mouth on that size.

Wasn't aware of the 30° limit on the hangers.

These are meant to be good for up to 45°
LSSR

or these
LRUZ

If your SE is happy with plumb cuts, are you not good to go without hangers?
What about truss clips?

As Noseall had said, you could add a collar tight under the ridge beam connected to the rafter pair. Just means you'll have a flat ceiling.

decided to go with short collars screwed to the rafters, gap the same as the thickness of the GLULAM (115) then pushed the beam up to meet both collars and rafters at the same time. Only hope the BCO is happy with it, inspection next week. Why do SE's make things so awkward, like, wanting me to build the noggins into the panel? Much easier to fix a new rafter to the side of the gable panel and noggin that to the next rafter. I'd imagine that would be muchos stronger. The bottom of the rafter where the rafter meets what remains of the ceiling ties after we cut them back, timber triangles were cut and glued/nailed between the members before 18mm ply gussets were added both sides. It's quite a space - 6m high, 7.4m wide by 6.25m long.

 

[catlad]

Looks like an interesting project, is it going to be your new home?

 

[frslam]

Looks like an interesting project, is it going to be your new home?

No, I live in a recently built (2010) house approximately 50 metres away from this one. The house being renovated is my old family home

 

[catlad]

Not far to work then...