Joists not resting on RSJ

[mjsx]

So I recently replaced a structural wall with an RSJ. All fine except some of the  wooden joists are not actually resting on the RSJ.

 

This is sort of expected in that the RSJ is perfectly level but the wall that was there before was not but it’s a bit strange you can slip paper through the gap.

 

I guess they will eventually settle over time (only a few mm in it) but is that going to crack plaster or tiles something once decorated? Should it be shimmed or something?

 

 

[Nickfromwales]

Cut hardwood shims and smack them in until they won't smack any more  

Make the shims for each gap, in a large mitre saw, and have the open gap as the start size of the shim, and then the shim doubling in thickness over the depth of the purchase point.

Apply some resin based wood glue to the two mating timber faces, immediately prior to fitting them, and job's a good 'un  

Edited February 20, 2023 by Nickfromwales
bold bits added

[George]

This is why I prefer mechanical connections like joist hangers. Any way of getting a small angle/cleat attachment to connect the joists to the beam?

[Nickfromwales]

3 hours ago, George said:

This is why I prefer mechanical connections like joist hangers. Any way of getting a small angle/cleat attachment to connect the joists to the beam?

Waste of time, imho. Shims are perfect for this, cheap as chips and easy to DIY.