Floor Joists via Hangers on Ledger Boards - Both sides?

[HitchinHome]

Any help would be really appreciated on this one!

We're currently completing a double side extension and I'm looking to install the first floor floor joists via hangers on ledger boards. The original plan was to fix the joists to a ledger board via hangers on the existing house, then lay the joists on the blockwork on the new wall as the extension goes up. However, this option on the new wall will not only delay the bricklayers from cracking on, but also I've read BC don't like you doing this nowadays as the timber can shrink over time.

So - my question is - can I fix ledger boards on both the new extension wall and the existing house and fix hangers and joists to both sides using this method?

I only ask as it feel like the whole floor will be floating.

Attached is a picture of the kind of fixing I had in mind.

Appreciate any thoughts.

 

[darkkent8]

Yeah i would say thats fine - just check with building control the spacing of the bolts into the wall

Also would make it better if the ledger board can sit on the wall either side too

 

[HitchinHome]

Thanks for the quick reply! By the wall either side, do you mean so that the ledger board then runs the whole perimeter of the floor? That's a good shout if so!

Also, regarding the bolting into the wall. Would you recommend something like an anchor resin with an M12 threaded rod and then bolted through, every 400mm centres. Or is that overkill?

Thanks again!

 

[darkkent8]

Yeah if its sitting on the brick work then thats taking most of the weight - the bolts into wall would just be extra security

Well the building control would never ask for more less than 400mm so going with that is a safest bet - however 800 centre is enough i would say

Anchor resin is good too - M10 or M12, again if you are trying to get on without BC coming out then go M12 then you are safe

 

[HitchinHome]

Ah I see what you mean about sitting on the wall either now. Unfortunately I don't think that'll be possible. So the floor would be held solely by the ledger boards and resin fixings. This still be ok do you think?

 

[darkkent8]

Yeah thats fine - if in doubt give you building control officer a call - they won't mind you asking!

 

[HitchinHome]

Thanks - really appreciate your thoughts.