Osb sheathing RSJ and window

[junglejim]

I’m building a timber frame home.

we have a large opening at the back for bifold doors which is framed with an RSJ.

 The window installers have said they can’t fit until this is sheathed in wood so looking for advice on the best way to do this. Externally I was going to add wool insulation, noggins then osb but haven’t really thought about bringing this into the reveal. Any advice etc greatly appreciated.

 Thank you

[nod]

There talking rubbish What they should have said it’s easier for them to fit with ply lining

If you need to fasten anything to the rsj You can shot fire nails or Tek screws