Raising level of loft floor

[biosh]

I'm about to have 250-300mm of insulation put in the loft. I need to raise the rafters(?) before this is done so that I can then lay a floor in the central area so that I can continue to use it for storage. there is currently no floor, just the clear rafters and ceiling beneath.

I'm thinking that the easiest way of doing this would be to put in some planks on their edge (? 50mm x 200mm) perpendicular to the current rafters and then floor them when the insulation has been laid.

Any ideas about how I should construct this and connect it to the current rafters? Or any useful weblinks?

Thanks

[stoneyboy]

biosh,
Insulate the existing loft to the top of the existing joists, fit your new planks at right angles to the existing rafters and pin the ends of the new planks using two planks parallel to the original rafters.
end