TIMBER JOIST

[showtime247]

i have 2 questions related to flat roof joists.

joists 4x2 400mm centres

Q1: Can the joist sit directly on top of steel UB then block work either side and above or is a timber wall plate required?

Q2: wall plate / leadger board connected to existing cavity wall, what size threaded rod is typically used M12 ? and i assume centers will also be 400mm staggered with flat plate washer and nut?

 

[showtime247]

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[^woody^]

You don't have wall plates with flat roofs

You don't build masonry on timber wall plates.

M10 bolts at 500 or 600 centres will be fine. No need to stagger.