Shopping List

We’re going to include two short lists of the materials you’ll need, based on what build you’re going with. We’ll explain why in the details below. But if you need a quick shopping list while you’re at the hardware store, here you go:

2 Layer Platform

2 Sheets of 4’ x 8’ Plywood, 3/4” Thick, CDX, RTD, or OSB Grade

1 Sheet of “nicer” 4’ x 8’ Plywood, 3/4” Thick, BC or AB/AC Grade Hardwood

1 Sheet of same “nicer” plywood, ripped in half to 2’ x 8’ (for corners)

1 4’ x 6’ Horse Stall Mat, 3/4” Thick, Pebble or Flat Texture Top

Box of 1 1/2” #8 Exterior Wood Screws

1/4” Flat Washers (8-12 per platform)

Utility Knife aka a Box Cutter

Straight Edge, a Level, or a PVC Pipe

Tape Measure

32oz Can of Oil Based Clear Semi-Gloss Polyurethane

Paint Roller and Head Cover

Plastic Paint Tray

3 Layer Platform

Everything listed above

2 Additional Sheets of CDX, RTD, or OSB

Box of 2” Exterior Wood Screws

2 Layer vs. 3 Layer

At HMB HQ, we’ve recently refinished our training platforms after some damages to the bottom layers. Because we’re a training facility, and not a garage, we have a lot more platforms to build. Which means great material needs and greater cost. These conditions dictated why we went the route we did, and may not apply to you.

For starters, our entire lifting area has a base layer of horse stall mats. We were lucky to come into a lot of rubber for very cheap ($10/mat). Horse stall mats are typically the most expensive part of your building process, retailing at Tractor Supply currently for $44.99 each. A sheet of RTD plywood that we would use for an extra base layer on these platforms, runs just over $20/sheet. Since our rubber cost half that much, and we didn’t want any exposed concrete between platforms, we decided that keeping our floor entirely covered in rubber would be enough, and we wouldn’t build an extra base layer out of wood for our platforms.

That’s the economics of our decision, and honestly the rubber will do a superior job of protecting the floor from damage. If you’re going to be in a gym or commercial setting, you likely have already invested in thousands of dollars of rubber flooring, and I think a single base layer will be just fine here. If you’re building your home gym, you probably don’t have endless rubber, and wood will cost you less than half of the rubber equivalent. I’d recommend going for the second model design.

Plywood

For your base layers, you just need 4’ x8’ sheets of 3/4” plywood. This will probably come in 23/32” sizing, since it’s lower grade. You’re looking for CDX, RTD, or OSB sheets. RTD claims to have superior performance against temperature and humidity fluctuations. I don’t know if that’s true. What I do know, is that they look and cost about the same as CDX, and is easier to find. OSB will be difficult to find in 3/4” sizing, at least in my area. It is cheaper, and poorer quality, but will honestly stand up just fine. The biggest concern will finding it thick enough, since it usually comes in just over 1/2” at my hardware stores. Go with what you like best, or, more likely, what is available to you.

The top layer is much more important because it will be the only part visible and need to stand up to your abuse. We have used BC grade plywood for a majority of our platforms. On two of them we went with AB grade Oak, because we happened to come into some for very cheap. Whatever you use, just make sure it’s a hardwood. Personally, I prefer the BC, because it’s sanded less and has a better grip. This is important if you want to stain or seal it with something, because the coarser texture will go over better once you’ve coated it. Finely sanded and finished wood won’t have anything to hold onto.

Stall Mats

For forever, the only kind of stall mat were the ones exclusively used for their intended purpose. The horse stall mats you find at your local Tractor Supply will have a flat, pebble top texture. It provides a little grip, but doesn’t affect the rolling of the barbell.

With the rise of Crossfit and home gyms, the concept of diamond plated stall mats seems to explode in popularity. These are fine, and actually what we have at HMB HQ as our general rubber flooring. However, these provide fluctuations in symmetry and height when setting up a barbell for a lift, and I personally don’t like them.

There are some mats, usually sold by actually rubber flooring or gym equipment companies, that have smooth, flat surface, as opposed to the typical pebble surface on regular horse stall mats. I only bring these up, because as a gym owner, I am now a Mopping Professional. These are by far the easiest to clean. Pebble texture eats up mop heads. Diamond plate leaves nooks and crannies for dirt to hide. Smooth reduces mopping time by 50%. These are usually priced the same, but may cost quite a bit to ship, which is why finding your local Tractor Supply or similar equine supply store is your best bet.

All that ultimately matters is that your rubber matches your top layer in thickness, so 3/4”. I would generally avoid actual rubber flooring companies. Surprisingly, they are generally the highest priced for lowest quality, and the most full of it.

Hardware

I’ve used all kinds of screws at this point in construction over the years. And you’ll probably be fine with whatever you like. For two layer platform, I recommend 1 1/2” screws or even 1 1/4” if you can find them. When you screw the pieces together you’ll likely find that the longer 1 1/2” may clear both layers on a 2 layer platform, but finding the 1 1/4” screws we talk about is difficult. If you’re doing a three layer platform, you will need some 1 1/2” screws and some 2” screws for different stages of construction.

Because my environment is exposed to the elements a lot of the year, being humid in the South and having big roll up garage doors, I wanted good screws. We went with exterior wood construction screws. These are affordable, but were still stainless steel, and will break down less over time. It is also a good idea to use the screws that have a star head, rather than a phillips head. You will strip way less screws and encounter way less frustration.

We used #8 1 1/2” Grabber Construction Screws, because they accomplished everything I wanted. These came with the star bit you need, and they claim to have “superior” threading with a counter sinking head. They gave me absolutely zero issues and did work pretty damn well. Would buy again. If you want to spend a little more money, the #8 GRK R4 Screws are even better because they have an additional coating and better counter sink threading under the screw head. They also come in 1 1/4” which is probably better for a 2 Layer platform. But either would work fine.

For the rubber, we recommend using some flat washers with your screws. Unlike wood which will take the threading of a screw well, rubber is usually made of recycled crumb from tires, and falls apart when penetrated. This isn’t that big a deal, but over time with repeated drops it will tend to jar the screws loose with such a small surface area.

To mitigate this, we bought some zinc flat washers, with a 1/4” inch hole that took our screws nicely. Now our rubber doesn’t shift as much and our screws aren’t sinking down.

Tools

Hopefully this goes without saying, but a good drill with basic twist drill bits. We used 1/8” bits to pre-drill our holes, which made everything go really smooth. Not a single stripped screw and no wood being split. I recommend corded if you’re doing multiple to avoid frustration, but your tools are probably nicer than mine. In fact, step one should actually be: buy a truck and good tools.

A good utility knife for cutting your mats. A trusty tape measure. Either a straight edge or level to draw lines against. A PVC pipe can work well in a pinch.

Polyurethane

A lot of weightlifters and coaches tend to not like a finished top surface. And I would count myself firmly in that camp. There really isn’t anything quite as nice as a naked wood platform to lift on, in my opinion. But there’s a few problems with doing bare wood.

If you intend to compete, guess what? You’ll never lift on bare wood, and I consider this to be a handicap. I can’t count the number of lifters I see complain about how slick the platforms are at national events. That’s the sport. Do it, or don’t. While you’re at, you should learn how to jerk, because that’s your actual problem.

This next bit applies to home gym lifters, but more to commercial gym owners: bare wood may become an aesthetic issue for your clients. It doesn’t look finished. It gets dirty and worn over time. Unfinished wood will chip away and make a mess. If you’re not climate controlled, your wood will warp, and this is even worse if you have even an ounce of humidity. Your top layer will fail. It is only a matter of time. Furthermore, bare wood wears down over time to become smooth, so the original worry of creating a slick surface becomes an inevitable result.

After being in many gyms, speaking to other owners, and lifting on different platforms, I decided to try Polyurethane in a limited dose. We experimented on some wood runners we have drilled directly into the floor, primarily for squatting. After over half a year, I’ve been pleased with their performance. We did 1 coat, which isn’t the amount you would see in a very nice collegiate setting with extra slick platforms. This left the grain of the wood still available to the touch. They retain their original wood color and don’t warp. They’re also cleanable now without worrying about the effects of moisture.

We used Varnathane Oil Based Clear Semi-Gloss Polyurethane. You can use a variety of methods to seal and protect your wood. This provided the best mix of performance, maintenance, and aesthetic I wanted from the wood.