How to Build a Garage Gym
How to turn a garage into a gym: prepping and sealing the floor, flooring, heating and cooling, preventing rust, layout around a car, and the equipment to buy.
To build a garage gym, prep the space first: clear it, fix electrics and lighting, seal the concrete and lay rubber stall mats. Then add a rack (folding if you park a car), a bar and plates, a bench and storage, and plan for heat, cooling and rust.
A garage is the classic home gym: room for a rack, floors that can take dropped weights, and no neighbours below. It also comes with problems a spare room doesn’t have: cold, damp, dust and a car. This guide covers the prep owners on r/DIYUK, r/GarageGym and r/homegym say makes the difference.
1. Prep the space
An owner on r/DIYUK who converted a garage summarises the steps: strip everything out, move any sockets and sort the electrics while it’s empty, vacuum and scrub the walls and floor, fill holes and level the floor, then paint or seal the concrete. Sealing stops a lot of dust. Bright LED lighting and a mirror make a garage feel like a gym rather than storage.
2. Flooring
Lay ¾″ rubber horse stall mats over the sealed concrete. Owners are blunt: look at horse stall matting, not “gym” matting, because it’s far cheaper, and get rubber, not foam, because foam doesn’t last. Tractor Supply’s 4 × 6 ft mats cost about $2–$2.60 per square foot. See best gym flooring.
3. Heating, cooling and insulation
Garages are cold in winter and hot in summer. Owners on r/DIYUK suggest insulating the garage door first (kits or foam board), and if you don’t need the door to open, building an insulated stud wall behind it. Use a thermostat-controlled heater, and a fan or air conditioning in hot climates.
4. Rust and humidity
Humidity rusts bars and plates. Run a dehumidifier, pick stainless or coated bars (see best barbells), and brush and oil bare steel occasionally. One r/DIYUK owner warns that cold iron plates sweat in humid air and leave puddles on the mat. Owners with uninsulated sheds and outdoor setups report dumbbells already showing rust.
5. Equipment and layout
- Rack: a power rack like the REP PR-4000 if the space is gym-only; a folding PRx Profile Pro if you park a car. See best squat racks.
- Bar and plates: a Rogue Ohio Bar and Echo bumpers.
- Bench: an REP AB-3000.
- Cables: rack-mounted cables keep the footprint small; see best functional trainers.
- Cardio: an air bike or rower handles cold garages well; see best exercise bikes.
Leave space at both ends of the bar for loading plates; owners note a bar too close to the wall makes loading awkward.
6. Storage
Wall-mounted plate storage, bar holders and hooks keep the floor clear, which matters even more if the car comes back in at night.
Next steps
See home gym ideas for layout inspiration, or our home gym setup guide for the buying order.
Frequently asked questions
How do I turn my garage into a gym?
Clear and clean the space, sort out electrics and lighting, seal or paint the concrete, lay rubber flooring, then add a rack or dumbbells, storage and a mirror. Owners on r/DIYUK who've done it say to plan heating and insulation early, because garages are cold.
What flooring is best for a garage gym?
¾-inch rubber horse stall mats over sealed concrete. They're cheaper than gym-branded mats and tougher than foam. Owners say foam interlocking tiles don't last under weights.
How do I stop rust in a garage gym?
Control humidity with a dehumidifier, choose stainless, cerakote or coated bars, brush and oil bare steel occasionally, and avoid cold iron plates in humid air, which can sweat. Owners with uninsulated spaces report rust on dumbbells and plates.
Can I fit a gym and a car in a garage?
Yes, with a folding wall-mounted rack like the PRx Profile Pro, which folds to 4 inches from the wall, plus wall storage for plates and bars. Owners building REP Ares wall-mounted setups do the same to keep room for a car.
How do I heat a garage gym?
Insulate the garage door first, then add heat. UK owners on r/DIYUK suggest insulating the door with a kit or foam board and using a radiator or heater with a thermostat. In hot climates, a fan and a portable or mini-split air conditioner make summer training bearable.