Gazebo footings

[Chumley]

Hi all,

Couple of questions about a gazebo...

If I was to make a square structure with a post on a stirrup in each corner, I guess I would bury the stirrup in a 600x600x600 block of concrete (based on what a builder did for my carport). That would give me .864 cubic metres of concrete to hold down the structure. What I plan to do, as I want a suspended floor, is to have 5 bearers to define the hex shape (see attached .jpg) - if I put 11 stirrups as in the diagram and used 450x450x450 concrete blocks it would give me just over 1 cubic metre of concrete holding down the structure. Is this valid/sensible/logical?

The short bearers will be 1600 long, the centre bearer 3200 the other 2 will be 2400 -- I plan a stirrup at the end of each bearer and one in the centre of the long bearer -- I will put the same number of joists going the other way, then floorboards going the third way (if you know what I mean). Bearers will be 100 x 75 treated pine LVL, joists 100 x 50 treated pine LVL, boards 50 x 19 hardwood. Can anyone tell me if this is enough to stop the floor from 'bouncing'?

Cheers,
Chumley

[pawnhead]

Sounds like overkill to me. Your joists will span 1.8m.

I'd eliminate the intermediate footings. Just one in each corner and one in the guts. Run a 4X3 bearer around the perimeter, and one through the middle, then butt your 4X2 joists in between them at the same level, @ 450mm centres. Use universal fasteners at the butt joints.

You'll use a lot less timber, and less footings this way, and it will pass the code.

[Blocklayer]

Dunno about the bouncey floor and footings, but this online gazebo calculator might come in handy for the dimensions to set it out.
http://www.blocklayer.com/gazebo.aspx

I'd appreciate any feedback on it, if you use it and have any suggestions
.
.

[Chumley]

Hi Pawnhead, rushed picture this time, but do you mean something like in the attached - with the floorboards added left-to-right? And when you say universal fasteners, do you mean something like joist hangers?

Blocklayer, I'll check your calculator over the weekend, I'm actually at work (coffee break ).

Thanks,
Chumley

[pawnhead]

That drawing looks better. Joist hangers would do the job, and it would look neater from the edge having it all at the same level, not having the ends of the bearers exposed.

[Chumley]

Hi John,
Thanks for the advice - I've been given the go ahead by swmbo, so I'd better get on with it now.
Cheers,
Chumley