How would you board this section of loft?

[turpis]

Hi all, I'm planning out how to board a small section of my loft above the hallway / landing - pic below - and wanted some other opinions.

The area is 1600 x 3700, the ceiling joists are 75x50, at approx. 400 centres, and the purlin is 175x65.

Main problem I've got is there's a large purlin / brace running between both party walls that the ceiling joists are nailed into for support across their span.

I'd like to have 200mm space below the boards so it can be fully insulated.
I don't want to load directly onto the ceiling joists as this will almost certainly deflect and crack the ceiling in the future.

Best idea I've got right now is to use joist hangers on the party wall (L) and internal wall studs (R) and run new joists between, spanning the purlin with the boards.

 

[pcaouolte]

Loft legs?

 

[turpis]

Loft legs?

Like I said don't want to load onto the ceiling joists

 

[pcaouolte]

Sorry, I missed that bit. I can't help then as all loft flooring I have installed has always added load onto the ceiling joists (and never caused them to deflect by any detectable amount).

 

[cdbe]

Nothing wrong with your proposal, easier to use a ledger board on the left and sit the new joists on blocks on the stud wall. You'll need to trim round the opening, and it looks like the existing trimming round the hatch is defying gravity.

 

[turpis]

Nothing wrong with your proposal, easier to use a ledger board on the left and sit the new joists on blocks on the stud wall. You'll need to trim round the opening, and it looks like the existing trimming round the hatch is defying gravity.

Yeah I didn't notice the dodgy trimmer until I posted the photo - not my work!