Seeking advise on building a deadlift platform

[Clay Simczyk]

If you are concerned with moisture, you don't need plywood at all. One layer of hose mats would work just as well and be easier to move should you find a better place to workout.

[Charlie Davies]

Yeah, the platform on a home gym is not going to see all that much wear and tear.

How many sets of deadlifts will it take to wear out a 1" thick vulcanized rubber mat? More than my spine has left!

The hard part for me was making a flat & level spot in my garage. It was quite strongly sloped. Throwing down some strandboard, plywood, and rubber matting on top was trivial.

[Eric Davis]

I would consider putting a vapor barrier under it. Just a piece of visqueen or a waterproof paint type application for the concrete. I have a very dry garage and I did not use a barrier. My platform, OSB with plywood on top, warped up about 3/4” on 3 of the edges. I’ve been told this is from the moisture that is still in the concrete, despite being very dry. A barrier seems like easy and cheap protection.

[Giri Kotte]

This one by Alan looks great:

That looks like a good starting point, in line with my needs.

Giri,
You're overthinking this. Buy some horse mats and some decently straight 3/4" plywood and attach everything with screws. I wouldn't even bother gluing it. When you start seeing issues, fix them. Eventually, you may want to build a new one based on what you learned, but you should be ok with model 1.0.

Glue etc. are a way for me to avoid buying exterior grade of wood instead of the more expensive marine grade.

If you are concerned with moisture, you don't need plywood at all. One layer of hose mats would work just as well and be easier to move should you find a better place to workout.

Yeah, the platform on a home gym is not going to see all that much wear and tear.

How many sets of deadlifts will it take to wear out a 1" thick vulcanized rubber mat? More than my spine has left!

The hard part for me was making a flat & level spot in my garage. It was quite strongly sloped. Throwing down some strandboard, plywood, and rubber matting on top was trivial.

I need some sound damping too. I live in an apartment.

I would consider putting a vapor barrier under it. Just a piece of visqueen or a waterproof paint type application for the concrete. I have a very dry garage and I did not use a barrier. My platform, OSB with plywood on top, warped up about 3/4” on 3 of the edges. I’ve been told this is from the moisture that is still in the concrete, despite being very dry. A barrier seems like easy and cheap protection.

That's a concept I wasn't aware of. I will check the utility and cost.

[Giri Kotte]

*Glue etc. are a way for me to get away with buying exterior grade of wood instead of the more expensive marine grade.