New concrete floor inside a Garage

[JohnS]

For a number of reasons I need to lay 100mm of premix concrete on top of my existing concrete garage floor(6m x 6m).
Do I need to leave any expansion gaps?
But my real question is:
Since it is inside a building, what formwork do I need and where do I lay it?
How do I level and tamp it? Do I just walk over the wet concrete and work out towards the door since I can't get at it from the sides?

[stoneyboy]

JohnS,
If you are good with a large level then lay the floor without guides. Otherwise use level guides for tamping and move them and fill as you work across the floor.
end

[TheDoctor4]

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