Convert concrete garage floor for use as gym

[Strubo]

I plan to convert an attached 6*6M garage into a gym, Iwill use free weights and a max loaded 600kG rack.

 

The garage floor is concrete, I would like to insulate the floor and bring it up the the house floor level, which means I have around 100mm for insulation.

 

What floor make up would the group suggest?

 

I was wondering if a floating floor would be possible, however as room will be used as gym, this might not be possible. In that case was thinking 100*47mm treated timber joists on top of the concrete, at 400 or 600mm centers.

 

I plan to use 20mm rubber mats as the floor. What would you reccomend below the mats, Plywood or T&G circular board and what thickness?

 

Thank you in advance for any help

[Andehh]

From my layman's opinion....I'd prob opt for 80mm PIR, 20mm tongue & groove chipboard glued & floated on top of PIR.....then I'd prob use doubled up rubber mats to absorb the blow of dropped weights. I imagine that'd make the whole room really bounce if you are not careful!