Loft floor joists questions for storage and model railway Information and advice on lofts and loft conversions. Find solutions and post your questions here...

[Rooftop]

Hi

Have a 6 x 7m loft space currently with 4” x 2” ceiling joists

Looking to have access for storage and a model railing way setup and maybe a desk to use from time to time

Which option is best

1) add new joists in parallel with existing from wall plate to wall plate with load bearing walls in middle (2.4m joists joined with M12 + joist connectors) 18mm OSB board for flooring which size C16 could I get away with?

2) add another 2-4” on the existing ceiling joists (at 90 deg angle on existing) with 18mm osb flooring

Thanks in advance

[stoneyboy]

Hi rooftop,
For option 1 you would probably have to use 47x120 joists, the biggest problem would be re-routing pipes and cables and any insulation. Option 2 has its attractions because none of the relocating/re-routing would be necessary but you may have to use fixings at every cross over. You would need to take the advice of a structural engineer to check whether either are sound proposals.
Regards S

[Rooftop]

Thanks for that.

Excuse the silly question but which should the new flooring joists go?

https://freeimage.host/i/UpnWqQ

Orange or green?

Chimney breast has been removed and is on the right of the picture (party wall)

[stoneyboy]

Hi rooftop,
If you are going for option 1 then the green or option 2 the orange.
Regards S