Apologies for posing another thread on low level decking. I have read through number of discussions available and gathered most of the required information. Just got few last items that I need expert advice on.
I am planning to build deck over existing exposed aggregate concrete with 1.2m overhang on the grass area. The concrete are is 4.5m x 2.4m with 120mm depth from the house floor level. The deck I am planning to build will be 4.5m x 3.6m (2.5m concrete + 1.2m overhang).
My plan is to:
- Use 90 x 45 H3 structural timber with joists spaced at 450mm. This will allow me 11mm offset from existing concrere if 19mm decking boards are used (120mm - 90mm - 19mm = 11mm)
- Use galvanized L brackets fastened with dynabolt every 1m of the joists on alternative sides
- Use 4 Pryda Post Anchor Stirrups along the long edge of the deck to support overhang area
The advice I am after:
- Would 90 x 45 H3 be adequate considering the overhang area? I am constrained by the height, but can use 90 x 90 if required.
- Would 4 stirrups be sufficient to support the 1.2m overhang area, or should I install stirrups every second joist or so?
- 11mm height offset from the concrete is good enough for ventilation under the deck?
- When installing the deck board, how frequently should I be screwing the boards on to the joists?
