Joists into RSJ web or bolt on wooden bearer

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Ive got 197x47 joists to span a 4.6m gap for my flat roof. On one side there is a solid brick wall I intend to bolt a bearer plate to and use joist hangers off that. On the other side is my 178 h RSJ.

Should I notch the joist end into the web of the beam, probably nearly 50mm off, or bolt a wooden bearer plate to the beam and use joist hangers off this as I will with the other end? If the latter, I already have 6 bolts through joining the pair of 178x102 beams. I could simply get longer bolts if this would suffice.
 
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To explain my situation better I have used my limited sketchup skills..... Would you go for top diagram or bottom diagram fixing? Obviously I wouldn't stick the joist directly over the bolts.
RSJ joists.jpg
 
Bottom diagram. Wedge first beam into the RSJ and use gripfil to keep it in place, but leave the existing bolts in place, and drill cutouts for them. If the wedged beam sits proud of the RSJ, then I'm not sure I'd bother with the second one. Wrapping the joist hanger over the top isn't desperate, but you could drill into the RSJ with a titanium or cobalt drill to fix over the top. Makes sure you wedge any gaps between the roof joists and the hangers, then the wedged beam in the RSJ can't go anywhere. I'd be inclined to make sure that the RSJs are held together as tight as possible, and whilst you could use a large washer under the wood, I'm not sure it's the best way to do it.
 
Timber in the web, then instead of that timber across the front, fix a 4x1 on the top of the beam and hang off that and fix to the web timber.

Why can't you use a single deeper beam or column as a beam?
 
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Thanks for the ideas. I suppose I should have mentioned that the RSJs are already in place and have bricks sitting straight on top of them. Putting anything on top ain't an option.

The reason for my thought about the second timber fixed over the web timber was for better fixing for the joist hanger. So you think just face fixing the hangers on the inserted web timber will suffice?
 
That's what I think people are suggesting. I was just a bit worried about simply surface fixing the joist hangers. The second timber was meant to enable the hanger to be folded over the top and fixed for extra security.

Next question - can I screw the joist hanger on or does it have to be nails for their shear strength?
 
I nailed mine to the face and top of the timber and wrapped them over the back before I bolted it into the RSJ.


I had to trim about 5mm off the bottom 25mm of the joist so it didn't hit the RSJ because the timber I bolted in was a couple of mm short of the outer edge of the RSJ.
 

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