Two measurements decide most of a small home gym, and neither is the size of the room. The first is the clear floor you can keep empty; the second is your own overhead reach. Take both before you shop.
The two numbers, and how to take them
Clear floor. Stand in the room and mark out the largest rectangle that has nothing in it and needs nothing in it. Leave out the sofa’s footprint, even if you plan to shift the sofa every session. Multiply the two sides. Everything below runs on that figure.
Your overhead reach. Stand inside that rectangle, hold a dumbbell or a broom handle at arm’s length above your head, and see what it clears. Ceilings vary and so do people, so a general figure cannot settle it and there is no use looking one up. If your hand and the light fitting are in disagreement, overhead pressing happens elsewhere in the flat, or it happens seated.
The mistake the tape catches
The rectangle comes out smaller than people expect, for a reason that is easy to miss. They measure the room, subtract the furniture and stop there. A room’s usable floor is what is left after the furniture, the walking route and the door swing.
The other half of the mistake is order. Shopping lists for this get assembled by category, something for cardio, something for strength, something for mobility, and then bought more or less at once. In a small flat I would buy in a different order: by how much of the room each piece occupies for good.
Three thresholds of clear floor
These are my planning bands; no standard sets them.
About 4 m2, roughly 2 by 2. A mat and a dumbbell tray against the skirting. Squat, hinge, press, row, plank, stretch. No bench in full extension, no rope.
About 6 m2, roughly 2 by 3. The band where a small gym stops feeling like a compromise. Mat, tray, a folding bench open, and half a metre to walk around it.
About 8 m2, roughly 2.5 by 3.2. The bench can stay open between sessions, and a step or a compact bike fits.
Plan for 6 if you can. Below that, every piece has to argue for its footprint. Above it, storage between sessions limits you before floor area does; that is covered in equipment storage.
The constraint that reorders the list first
If somebody lives underneath you, what you are willing to put into the floor decides the kit, and it decides it before floor area gets a say. This is not a figure you can look up or measure from inside your own flat, and you do not need one, because the ordering it produces is the same either way. Weights that get set down rather than dropped are in. A walking pad is in. Bands are in. A treadmill at running pace above an occupied flat is out, jumping is out, and dropping anything is out.
The neighbour that matters here is the one below. Impact goes downwards through the structure. What reaches somebody through a shared wall is a different and mostly airborne problem with a different fix. The quantities behind the downward side, what each one measures and what none of them can tell you about your particular building, are set out in home gym flooring.
Four pieces, in the order I would buy them
1. A mat. Gaiam’s standard runs 68 by 24 inches at 6 mm, so 173 by 61 cm. That rectangle is your working footprint for everything done on the floor, and it is the piece that makes the other three usable. It is also the cheapest thing on the list, so I would buy it first.
2. One pair of adjustable dumbbells. A BowFlex SelectTech 552i measures 43 by 21.2 by 22.8 cm per dumbbell and covers roughly 2 to 24 kg each, replacing a rack of fixed pairs in the footprint of two shoeboxes. The number to note is the 22.8 cm height, because that is what keeps the pair from sliding under most bed frames, so plan a floor-level home for them beside the mat. The mechanism matters more than the weight range, and that comparison is in adjustable dumbbells versus regular.
3. A band set. Shoebox-sized, covering rows, presses and every load that sits below your lightest dumbbell setting. It is also what you train with on the days everything else stays put away.
4. A folding bench, if the rectangle allows. Steady’s ST123 fits inside one tatami, 1.8 by 0.9 m, in use, and weighs about 13 kg. The slimmest models fold thinner than that suggests: a Leading Edge LE-FFB2 goes to about 16 cm thick at a 300 kg rated load. In use is the figure that decides whether it fits your rectangle. Folded is the figure that decides whether you will bother, and the folded numbers live in equipment storage.
Those four cover squat, hinge, push, pull, carry and step, and between them they handle the muscle-strengthening half of the CDC’s adult guidance: at least two days a week working all the major muscle groups, alongside 150 minutes of moderate-intensity aerobic activity. Laid out along a wall, the mat’s 173 cm sets the length and the tray adds most of the rest, so the whole set lives in roughly 2 m of one wall: mat down the long side, tray at one end, bench behind a door, bands in a basket.
What to skip, and the reason
A barbell and a plate set. A full-length bar is longer than most small rooms have spare wall for, and the plates then want somewhere of their own. In a room this size the pair consumes the storage well before it consumes the floor.
A full power rack. Settled by the ceiling rather than the floor, and usually settled against the rack. Take the rack’s published height, add the room you need to get a hand over the pull-up bar, and compare that against the clear height you measured rather than against any general figure. Worked through with a manufacturer number in workout corner without a spare room.
A motorised treadmill, if you are above an occupied flat and want early sessions. A walking pad does most of the job with less of the problem. The A1 Pro folds from 143 to 82 cm long while staying 12.9 cm thick either way, which is a more honest picture of what folding buys than the word suggests.
Plyometrics on thin matting. A thicker mat protects your floor and does little for the ceiling below it, so jumping stays off the list.
Getting the room back
Five minutes from finished to living room again is the cutoff I plan to, with no stopwatch behind the figure. Past it, I would expect the reset to get postponed and the gear to stay out. The number moves with how much furniture is involved.
Design for it once and it holds: nothing in a deep cupboard, nothing stacked on top of anything else, nothing that needs a tool. Mat along the longest clear wall, tray at one end within reach, bench where it does not foul a door, bands on a hook. The room-by-room version is in organize fitness gear in a small apartment, and the corner all of this assumes is in workout corner without a spare room.
Sources
- BowFlex SelectTech 552i - published per-dumbbell dimensions 43 x 21.2 x 22.8 cm, about 2 to 24 kg per dumbbell, read 2026-08-29
- Gaiam Essentials Yoga Mat - published size 68 x 24 in x 6 mm (173 x 61 cm); the page publishes no weight. Read 2026-08-29
- Steady Japan ST123 folding bench - fits within one tatami (1.8 x 0.9 m) in use, about 13 kg, about 330 kg rated load, read 2026-08-29
- Yocabito - Leading Edge LE-FFB2 folding bench, about 16 cm thick folded at a 300 kg rated load, read 2026-08-29
- WalkingPad A1 Pro - published folded and unfolded dimensions (822 and 1432 mm long, both 129 mm thick) and 28.5 kg net weight, read 2026-08-29
- US CDC adult physical activity guidelines - 150 minutes of moderate intensity aerobic activity a week, plus muscle-strengthening activity on at least 2 days a week working all major muscle groups. The CDC site blocks automated access; both figures were confirmed from CDC page text reproduced in search results on 2026-08-29