For a 2 bay garage, allow about 380 l/min at 9 bar: a 7.5 kW piston compressor such as the E 75 in its 12.5 bar version is enough if air is used in bursts. With 3 bays the need rises to around 570 l/min, and the K 75 in its 10 bar version becomes the most comfortable choice, especially if air runs all day.
Our compressor for garages page covers the main machine types. Here we start from the number of lifts and end with a specific model.
One lift, one mechanic, one tool at a time
The number of lifts tells you how many mechanics can use air at the same time. Each one only has one tool in hand at any moment. So for each mechanic you count the hungriest tool they use.
Typical consumption figures, to check against your tool manuals:
| Tool | Consumption | Pressure |
|---|---|---|
| 1/2" impact wrench | 300 l/min | 6.3 bar |
| Air ratchet | 150 l/min | 6.3 bar |
| Blow gun | 150 l/min | 6.3 bar |
| Tyre changer | 150 l/min | 8 bar |
| Car tyre inflator | 100 l/min | 6.3 bar |
These tools work in bursts: a few seconds of tightening, then a pause. The receiver absorbs the peaks, so they can be counted at 50% of their consumption.
The calculation step by step
2 bay garage
- Hungriest tool per mechanic: the 1/2" impact wrench, 300 l/min.
- Counted at 50%: 150 l/min per mechanic.
- Two mechanics: 2 × 150 = 300 l/min.
- 25% safety margin: 300 × 1.25 = 375 l/min, rounded up to 380 l/min.
3 bay garage
- Three mechanics: 3 × 150 = 450 l/min.
- 25% margin: 450 × 1.25 = about 570 l/min.
3 bay garage with an air grinder (450 l/min, counted at 50%, so 225 l/min): 225 + 150 + 150 = 525 l/min, then 525 × 1.25 = about 660 l/min.
Pressure. The tyre changer sets the pressure for the whole garage: 8 bar at the machine. Add about 1 bar for losses in hoses and couplings, and the compressor must deliver at least 9 bar. That is the rule our configurator applies.
Which compressor for your garage?
| Your garage | Need | Recommended model |
|---|---|---|
| 2 bays, air in bursts | 380 l/min at 9 bar | E 75 in 12.5 bar, 0.9 m³/min, 180 L receiver |
| 3 bays, air in bursts | 570 l/min at 9 bar | E 75 HP, two-stage, 1.05 m³/min, 300 L receiver |
| 2 or 3 bays, air all day | up to 660 l/min at 9 bar | K 75 in 10 bar, 0.95 m³/min, 420 L receiver, built-in dryer |
| 3 bays with expansion planned, or a truck bay | over 800 l/min | K 110 in 10 bar, 1.4 m³/min |
E series piston compressors are built for intermittent use: they need rest time between cycles. With a need of 380 l/min against 900 l/min produced, the E 75 runs less than half the time, which is a good ratio. With 3 bays the gap narrows, and the margin of a screw compressor makes real sense. The K 75 is also quieter, at a stated 66 dB(A): useful when the compressor sits near reception.
If you plan to grow soon, the configurator has an expansion option that adds 20% to the need: for 3 bays, 570 × 1.2 = about 680 l/min. The K 75 in 10 bar still covers it.
Pitfalls specific to a multi-bay garage
An 8 bar compressor is not enough for a tyre changer. The S 55, for example, only works at 8 bar: it leaves no margin for a machine that needs 8 bar at its inlet. Choose a 10 bar version or higher.
One drop for two lifts. If two mechanics share one outlet, they wait or drag a hose across the workshop. Plan one outlet per lift, with the same quick coupling type everywhere.
Water in the wrenches. The more the compressor runs, the more condensate it produces. On a piston compressor, drain the receiver every day or fit an automatic condensate drain. The K 75 already has the dryer and filtration built in.
Piston or screw. If you are still unsure, our article piston vs screw compressor compares the two technologies in detail.
Enter your tools and number of mechanics in the configurator, or describe your garage in a quote request: we will check the calculation with you.
For your trade: Compressor for garages.