After moving into a house with a garage I've decided to fulfill my goal of having a home gym. One of the pieces of equipment I needed for that was a deadlifting platform. After looking around online for a bit I've decided to follow this guide by Alan Thrall and build my own. These are the lessons I learned from completing this project. Note that some or all of these might seem obvious to you if you build things like that regularly, but for me, it was all new.
You're going to need a lot of glue
Alan doesn't explicitly suggest the amount of glue you'd need but it might be more than you think. I ended up using about 1.3 gallons of wood glue for this project and it's possible I should've used even more.
Large sheets of plywood are annoying to handle by yourself
You might need someone else to help you align the two 4 ft. x 8 ft. pieces of plywood to glue them together. While I am sure it's possible to manage it yourself, if you can make things easier and have a buddy help you out, I'd suggest doing that.
Put a tarp under your platform
There's going to be a lot of glue oozing out of the platform. You can either wipe it away with a wet cloth while it's still liquid or try and scrape it off after it's dry. In the latter case if you have a concrete floor underneath the platform it is quite likely that the platform would get glued to it and you're going to have a rough time peeling it off. You can avoid some of these issues by placing a tarp underneath it.
Horse stall mats are heavy and hard to cut
I wasn't expecting this to be the case but a single horse stall mat felt much heavier to me than two sheets of plywood. Moreover, I suggest you buy a small handsaw to make it easier to cut the pieces you need. Alan cuts his mat with a boxcutter knife, I can't even imagine how long that would take given that even with a handsaw I spent about an hour cutting the two pieces I needed.
Pay attention to the corners and clamp down your plywood
If you don't put enough glue in the corners of your plywood and you don't use clamps or an adequate amount of weight on top, chances are your corners will pop up as the glue in the middle begins to dry. You don't want that to happen. I thought I could get away with just place random semi-heavy household items on top of the platform, but I think I'd have a much better time if I had actual weight plates or clamps to press the two sheets together evenly. Also, as the glue dries the plywood might shift around a bit, you want to prevent that from happening, hence the need for weight/clamps.
Take your time
I suggest dividing this project into distinct steps that you could perform with some breaks in-between. You don't want to rush this since you'd need to let the glue dry, let the wood stain get absorbed, and so on. Doing this little by little over a couple of weekends worked pretty well for me.
This was a really fun project and I wouldn't mind doing it again sometime in the future. It's fairly simple so even if you're a beginner you will most likely succeed and build a decent deadlift platform. You can't screw things up too much, since it doesn't need to be perfect. As long as the platform is level and your barbell doesn't roll around, you did great.
I also want to thank my employer Mercury for establishing a wellness stipend we can use on our hobbies, it gave me that final push to go and attempt a project like this. If you want to come and help us build a bank for startups at Mercury, feel free to reach out!