Shed spec

Don't use 4x4 as joists, waste of money. I'd use the 4x4 as 8inch or higher blocks to support your 4x2 floor joists, can half lap and nail to joist if feeling fancy, or just butt them up to the joist from underneath, you'll need a slab under each one though, laid on compacted hardcore, can go overkill if you want but it is only a shed. You can cut the 4x4 posts longer if you'd like to protect the shed from water ingress at ground level, but you'll have to build steps up then.

3x2 will be fine for the roof, you said the shed is 12 foot by 8, so even at the greatest span, an 8 foot length of timber won't be far off a reasonable pitch, put collar ties on the rafters to strengthen and eliminate sag. 400centres and sheathe the outside of the roof with 11mm Osb and you're laughing.

 

Have a look at these video's, there four or five , he gives some great advice on building a shed from walls to roof.

 

Good info, helps with my shed planning!

 

Hi, has anybody tried using 25mm aluminum square tube for the frame?

Have seen there various connectors that could be used with the square tubing etc to make the corners and join studs. Just wondering if it would be worth it costwise verse weight compared to wood?

 

Seen people use 8020 ali extrusion in vans where strength to weight is an issue but for a shed probably not worth it at £10/m