2nd story deck - footing size - engineer and council - Qld

Hi there,
I am drawing up my 2nd story deck plans to submit to the engineer and then to council here in QLD.

The deck is about 2300mm from natural ground level. And will be at the height of the house floor.

I am using 75 x 75 x 4mm posts and a couple of 90 x90 x 4mm gal posts on the corners which are to extend through the deck to form the stairs, ballustrades and a screen.
Setting these directly into concrete footings.

I'm wondering does anyone know what size footings would be sufficient?

I don't want to bother with soil testing but am happy to dig and mix more concrete so was thinking to just over-engineer them.

Would 400 x400 x 600 deep cover it?

And how deep am I meant to embed the steel post into the concrete?

Zonga

No roof.

Hi Zonga. When I had my single story extension designed, without a soil test a depth of 1m was specified. I thought that was crazy (and would require more than a two man auger) so I got a soil test done and 800mm deep was determined from that, and a 300mm diameter. Take from that what you will :)

And for embedment, for concrete stumps a 200mm pad at the bottom of the hole was also specified.

I took a similar approach when later adding a steel workshop with carport

wow, 1m is some serious digging.

looks like i might go for the soil test too.

thanks