A gym at home is super convenient, but some of us don’t have room in the basement, garage, or first floor, or we’re stuck in an apartment building. It’s this situation where you have to consider whether your upstairs or second+ story floor can support your gym safely.

Structural Integrity of the Floor

In the US, residential building codes require that every bedroom support 30 pounds per square foot (psf), and other rooms support 40 psf.

However, it’s ok if you exceed that for a portion of the floor. Each square foot doesn’t have to individually be limited to 40 lbs.

Think of it this way. Would you be afraid to have two 300-lb people standing very close together? It’s disturbing that they snuck into your home, but your sense is that you wouldn’t have to worry about the structural integrity of the floor, right? 

Would this scare you? Don’t judge.

The thing is, construction standards require that you can fill a room by loading every square foot to 40 lbs, like with a ton of 40 lb boxes. If some portion of the floor is bare, you can start stacking extra weight on the rest of the floor and it would be fine. The floor joists spread out the load. That’s how you can have a person of any humanly possible weight standing with feet together in a 1-sqft spot of floor.

So back to gym equipment. For a gym involving weights we recommend putting down 3/4″ plywood and rubber mats (ideally 3/4″ rubber mats) on top. The rubber spreads the load a little, aside from providing good traction, a comfortable amount of give, and preventing a dropped weight from punching through the floor. The plywood underneath spreads the load out much more. 

Think of all the large bookcases and hot tubs on second floors. Bookcases are generally against a wall where there’s more floor support, and that helps a lot. But still, if some of the room isn’t holding much or any weight already, your joists can take quite a bit more weight.

Often you can get away with up to 1500 lbs of gym equipment that does not involve any shock loads. There are probably some exceptions where you need to be more careful. I’m not a builder and don’t know much about it. But if we’re going to pick a number, that’s as good as any.

I recommend you get a professional (a structural engineer, ideally) to check things out and give you better advice than that arbitrary number. He can check out the spacing and size of the joists, and heck, maybe in an apartment building you’ll be lucky enough to be right over a steel I-beam. Or you’ll be unlucky enough to be in an old home that doesn’t meet current codes and barely can hold your weight, but at least fortunate enough to have learned that before you break through it.

If you’re dropping the barbell at all, the shock load goes way beyond its total weight, and you could run into trouble. We’ll get into that below.

Weights and Power Racks

Let’s look at a power rack / squat rack, olympic weights, and bench. I’ll give specific numbers here, and then you’ll see that the other types of equipment below will be even less of an issue.

An entry level power rack has about a 4’x4′ footprint.

Let’s say you’re a big guy and you bench press 200 lbs. 

A 130lb rack + 200lb person + 200lbs of weights + 100lb bench = 630 lbs. 

Divide 635 lb / 16 sqft and you’re at 39 psf. Sounds dangerously close to the 40 psf max, right?

Well, as we discussed above, this is spread out by the floor joists, and hopefully by your rubber over plywood flooring. So even if you add a certain amount of “shock load” factor as you drop the weights on the rack, it’s not a big deal, and any floor should be able to support this.

Another example: The popular Rogue RML-390F power rack weights 295 lbs, for a total live load of 795 lbs with the other stuff above. The footprint is 4’x4′, spreading the load out more. Put the numbers into the above formula and you get 50 psf. Not that much more, really. Again, that load will be supported beyond the rack’s footprint, so not a big deal. You probably also have it against the wall, so even better.

See below on deadlifting. That’s a different issue.

Deadlifting

Short answer: You can do it if you take certain precautions, but you’re going to scare the hell out of your downstairs neighbor.

This is what deadlifts sound like to your neighbor.

If you can always set it down gently you’ll be fine. But I’m not going to be the jerk that tells you to lift lighter weight for more reps so you can set the bar down gently. Deadlifts are your opportunity to do just a few reps with as much weight as humanly possible.

For setting a deadlift down hard, you at least need a couple layers of rubber mats or a lifting platform that is built with wood and rubber. Even then you could cause damage with enough weight. 

A platform or a few mats doesn’t do much for the noise. You’re going to scare the hell out of the resident below, resulting in some angry knocks on your door and eventually the brake line being cut on your car. To soften the noise, you would have to be dropping the weight on cushy and thick foam pads that totally absorb the impact. It would have to be so big and soft that you’ll have a hard time loading plates on the bar. And your starting height will be messed up. I mention this because I’ve heard of someone doing this, but I wouldn’t want to.

That’s just for deadlifts. Don’t even think about dropping cleans or snatches. That’s how you start the lift on the second floor and finish on the first.

Cardio Equipment

An elliptical or any kind of indoor bike is not going to cause damage. It’s not that heavy, not that noisy, and you aren’t creating any shock loads whatsoever, which is really where the danger lies in other equipment.

An air rower like a Concept2 will make noise, but more like the kind of noise where you could be keeping your housemate awake in the next bedroom, not the kind where you sound like you’re trying to break through.

A treadmill will shake the floor, assuming you’re running and not using it to walk while reading a book.

Home Gym Machines

Machines are not much of an issue, even if it’s the freeweight loaded type where you have a lot of weight plates sitting around. The machines don’t add much shock load even when you lower the weight arm or cable heavily. It’s not going to fall through the floor.

Preventing Noise

I have avoided talking here about the noise factor of all these types of equipment. That’s a whole different post and has more to do with keeping your neighbors and housemates happy than worrying about damage to your floor from all the weight.

See my separate post on the topic of how to work out in an apartment without making a racket.