Laying a decking over uneven slabs

[steve474]

Hi, hopefully someone can help me, I'm laying a 3.6m sq decking over a old uneven patio area, I'm using 6*2 joists but in large areas the joist doesn't touch the floor, what can I use to pack up between the old slabs and joist ? Could I use slate ? I know builders use this under RSJ. In places I can get my hand under

 

[Naduska]

You could scribe and cut/plane the timber to suit the slabs, that way you get all the timber to come into contact with all. The slabs, really easy.

 

[drpepe]

Concrete posts at each corner then build the deck suspended off the floor.

Will help prevent damp issues too.