Add joists or sister existing ones?

Hi all

I'm really stressed trying to figure out how to move ahead with this issue. Paid contractors to do it originally but they let me down massively

I am currently renovating a bathroom and need to sister existing floor joists to support the additional weight of a new bathtub. I am looking for advice on the best way to support the full length and bear the joist on the masonry end without causing excessive damage to the wall.


(Pic of the masonry wall end)

The Current Setup:

• New joist: 150x50
• Old joist 130x45
• Span: 2.9m
• End A (Bathtub end): Existing joists are notched into/onto a steel beam.
• End B (Wall end): Existing joists are notched into pockets in a brick wall.

The Problem: I need the new sister joists to have proper bearing support at both ends. The steel beam end is manageable (I'll just notch it?), but the brick wall end is difficult. The pocket already look wonky.

I know about masonry hangers, but the mortar line is super wonky, and I don't know how to tell if the bricks are strong enough for a wall plate. (It would have to be a small plate in between each joist right?)
Should I build a stud wall under it to support the joists?
Is sistering the joist the best option here? Should I add new ones in between instead?

I greatly appreciate any advice you guys can give me

4.5mins in you can watch sistering joists.



Then strong tie mini joist hangers but you will need to measure the width and see whats available.
Get the correct width of timber so it will fit in joist hangers.

You probably don't even need an end bearing. Sistering the joist, with bolts/nails at appropriate centers, will help to prevent the original joist from deflecting in the middle, under the weight of the tub. The weight of the bath won't cause the timber to shear off at the ends.

I've also made a T bar to lift joists level before strengthening if required.
That's if they will flex.
Maybe hardwood