I would put a special equipment pad/mat material over the area you want to set the treadmill. With running, I'd think without a thick grip type material the treadmill may move over time and scratch your hardwoods. I believe there are interlocking squares you can use.

It hasn't shifted at all, and yes, it is pretty heavy. No dents yet. :)

The equipment mat takes the denting instead of the floor.

Hi I have just had the whole of my downstairs tiled (porcelain)on top of my old floorboards. Would anybody recommend putting a treadmill on top of the floor and if so would i need anything in particular to do so. Any help would be appreciated. Thanks Paul

It all comes down to deflection rating. If the joist/subfloor system is good enough to handle tile...it is good enough to handle tile+treadmill. In theory this is just fine.

But of course that assumes you had the joists/subfloor thickness assessed prior to installing the tile.

Yes the floor was really solid, we also put down 12mm cement boards with a good quality flexible adhesive. Do you think with a good quality rubber mat down we will have any problems?

Cement board doesn't add structure...just height. Rubber + tile is no problem. Rubber + hardwood = BIG problem.

Alwaysonbudget, can you share where you got the mat?