workshop construction

[cockney]

Hi i would like some expert advice if you dont mind.i am wanting to build a 28'x16 workshop for my self so here's how fair i got in the planning of it but i am a little bit stuck.
so i was going to start of with 4x2 for the floor joist supported by 16" collums which i think should be ok. the wall i was going to make out off 4x2x8' and cladding around the outside.now this is where i am to to sure what to do because i want a flat roof. so i was thing of put up 6x2 joist by 16' long then osb board the felt for the roof cover.is the 6x2 joist big enough for that span ? if not could someone please tell me how i can do this cos i keep reading about snow loads by the why i live in scunthorpe north lins.so any help or plans or just advice that anyone can give me would be very much appreciated very much Tom ([email protected])

 

[Lord Kitchener]

Just one joist? Are you sure?

I presume you must be working from a plan of some kind, any chance you could post it for us to have a look at?

Have you done this sort of thing before?

 

[cockney]

hi no i was going to put up 15 6x2 joist across the 16' no i just got the drawing that i have made my self on paper. yes i have dont small sheds in the past noting like the size of this tho

 

[beaver]

Hi Cockney
Sorry i dont know the size you would need, but i do know that 6x2 will not be strong enough my current workshop is exactly that size with 15 well bowed roof beams holding up the same osb board. as a minimum i would suggest noggin out the 6x2 or uping to 8x2. i am about to rebuild but will not have the same problem as i will be turning the old beams crown side up and laminating them to new ones (6x4)

 

[Woodchips2]

Hi Cockney
Old rule of thumb for flat roof joists was span divided by 2 so 8x2 joists at 16" centres and floor joists span divided by 2 plus 2 so 10x2" at 16" centres. However modern Building Regulations may not agree with these approximations because you are supposed to take account of possible loadings. The guys in your local Building Control Department may give you some advice but may also say you need planning permission and Building Regs approval :twisted:
Regards Keith