Deck joist size

[No skills]

Greetings all.

I have a very small deck to build 6'x10', any other decks I have built have been a bit bigger and I have tended to use 6x2 for joists (beefing up where needed). Given the small size of this project doing everything in 6x2 seems excessive.
What I was considering doing is a 6x2 outer frame with a doubled up 6x2 in the middle, will 4x2 be suitable for the less than 5' span that's left?? (on 16" or less centres).

I'm not trying to cut corners and will go up on timber size if I need, but do I need to?

Loading is just people and plant pots, no mini hot tubs or anything

Thanks

 

[RobinBHM]

I seem to remember span tables for 4inch joists have a max span of about 6'0

A crude rule of thumb is half the span +2", so a 5'0 span would give a 4.5inch joist.

 

[blackrodd]

Down here in Sunny Devon, we have a similar rule of thumb for joisting but I was taught half the span +1",
But as the joisting is all 45mm now, not 2", I rather think that + 2" is probably better as Robin's rule.
after setting out the joists, a good, snug line of bridging, or noggin goes a long way to stop joist flexing.
Strike a chalk line along the centre of the 5' run, Nail or screw the bridging on alternate sides of the chalk line,
This gives better access for fixing each and every end.
This is for 16", or 400mm joist centres
Regards Rodders

 

[n0legs]

38mm x 97mm SC3/C16 @ 400mm spacing = 1.83M span
47mm x 97mm SC3/C16 @ 400mm spacing = 2.02M span

For dead loads not exceeding .25KN/m2

 

[No skills]

Thanks folks very helpful indeed

 

[Phil Pascoe]

It's a small deck. Work out how much you'll save, and think from there on ...

 

[No skills]

It will go some way to saving my back.