Replacing an old ceiling

[hsthmsking]

Hi, looking for some advice please

I've taken the ceiling out of a second bedroom of a traditional Victorian semi that we are currently renovating. Now that the ceiling is out, I'm looking to change the direction of the joists as they previously were. Main reason being that the previous joists ran the whole way across the width of the house (one bedroom and a hallway), from adjoining semi wall (brick) to exterior wall (brick) rested along stud wall in between and we want to put the ceiling of the bedroom back to its previous height whilst the ceiling of the hallway will go up to as close to the roof. Since we no longer have the option to run joists the whole way across I now want to run the joists of the ceiling in the bedroom front to back (perpendicular to as they previously were). I plan to use a timber wall plate and fix into the brick (not on top of) on either side of the roomand then run joists on hangers. Above the ceiling will then be used for storage, not a fully converted room but will be sturdy enough to take weight.

Main questions are;

Does this plan sound ok?
Is it ok to fix the wall plate into brick for this type of weight to be held?
What size wall plate should be used?
What size joists should be used?

Thanks, I've attached a photo showing what the plan of the new joists would be, apologies for the crappy markup on the photo. Just for illustration purposes

 

[danfre]

If the ceiling joists connected to the rafters you have probably weakened your roof, the ceiling joists help stop the spread of the roof.
Think you need to employ a structural engineer

 

[hsthmsking]

They weren't connected but thanks