I am fitting some new joists in my roof and will be bolting the new joists to the existing rafters. Both joists and rafters are 47mm thick.
After some advice from a friend (which may of course be incorrect!) I plan on using M12 x 110 hex bolts and timber connectors in-between:
My problem is I am unsure which combination of nut & washer to use. Some possibilities:
- split ring washer with standard hex nut
- flat washer with nyloc nut
Which is best?