All based upon “continuous span” with joists at 450mm between centres.
As many houses these days are built on concrete slabs, there is often a shortage of height available to build a regular decking substructure of stumps, bearers and joists etc. Indeed, many houses have a slab for a patio area set down only approx 100mm below the height of the main housing slab. Fixing timber battens directly to concrete slabs is regarded as a poor building practice due the moisture uptake into the batten which will rot out the batten way before its normal lifespan. This scenario has made it very difficult for people to enjoy the relaxed lifestyle of having a timber deck at their doorstep.
The clever people from KlevaKlip have released the Adjustable Joist Hanger. This product, the only one of its type on the market, not only lifts the joists off the concrete, but allows you to adjust the "top of joist height" from 80mm (using 60mm length bolts + 70 x 45mm joists) to 170mm (using 120mm length bolts + 90 x 45mm joists).
The KlevaKlip Adjustable Joist Hanger is registered for Patent approval. It is simple to install and can be used with suitably treated timber joists with a width of 45mm, and minimum height of 70mm.
Note: Hardwood joists should be screwed to the joist hanger rather than nailed.