Decking advice

[SIMONLEWIS]

Hi, I am very new to this site, just wondering if anyone can give me some advice on deck building. I am building a low level deck 10m x 6.9m. I'm told that joist hangers would be the way to go, but I am also told that laying joists on top of bearers is easier. Clearance is an issue, as i wont have a great deal of room under the deck.
Just seems like it would be a large amount of hangers, and a lot of timber to be cut if I went this way???

[Wood Butcher]

Unless you have to sit the bearers right on the ground using joist hangers is not worth it. You won't save any huge amount of timber and you then have the extra cost of the hangers. I think that you would only save about 3 inches of height using the hangers which is the thickness of the joists sitting in the bearers.

[SIMONLEWIS]

Cheers Rowan,

I currently have about 150mm of clearance, so from what i have read on the forum since i posted, it looks like this will be an issue. I have no problem in digging out another 150mm, as this is a big area and drainage shouldn't be a problem.So it would it be better to use the hangers to save clearance???????? Does using hangers alter the strnght at all?

[ThePope]

150mm clearance...
is that from top of ground to top of finished deck ?

[SIMONLEWIS]

yes, thats right

[SIMONLEWIS]

Just from what I have read on this site, I have designed what I think should work - I have attached a pic

[ThePope]

You have 3 choices basically...
1.Grab the shovel and start digging the whole area, you can then do bearer with joist on top. (heaps of digging)
2.Partially bury bearers inground and joist on top, (a little less digging)
3.Go with the bearers and joists at the same level using joist hangers. (no digging)

As I hate digging personally I'd be opting for the last choice, but is more work doing the framing. So your choice is what you hate less, digging or framing :)

[SIMONLEWIS]

Thanks heaps for that, I dont really like digging, so i think the third option is pretty good.

I was looking at using 100x75 for Bearers and 100x 50 (both F8) for Joists. would this be ok for 400mm spacing between Joists. Will I get away with a larger spacing between joists?

Promise thats my last question!!
thinking of using kempas ot merbeau on top.

[ThePope]

Bearers and joists are ok for the span and spacing you've drawn.
F8 100x75 max span 1800 (you have 1500, can increase that if desired)
F8 100x50 max span 1800

Spacing between joists depends on the decking type and thickness, but in general 450c/c is the norm.