hardboard or mdf or ply

[jake]

I need to cover parquet flooring as I need to put a hospital bed and hoist on it. Which is it better to cover it with hardboard mdf or ply

[gfretwell]

Any of them will work as long as it doesn't get wet. If it gets wet, water damage to the parquet will be the biggest issue

[Oren]

OP might tell the class his current sub-floor.

[Meanie]

As noted, any of them but any of them can still scratch the parquet floor if slid under a heavy object. I would put felt pads or some soft cloth between the floor and wood, then put hospital bed on the wood.

[clare]

I'd use a 1/4" plywood underlay - Okume (Mahogany) , not poplar