Lesson 3 of 8How lifts work
Machine room-less lifts.
A machine room-less lift is a traction lift with everything that used to sit in a machine room moved into the shaft or a landing cabinet. Here is where each part goes, and what that changes for the people who look after it.
What machine room-less means.
A traditional traction lift has a machine room, usually on top of the shaft, holding the machine, the controller and the overspeed governor. A machine room-less (MRL) lift is the same kind of lift with that room taken away. The machine is moved into the shaft, and the controller moves to a cabinet at a landing.
With a machine room
Machine room-less
Describe these diagrams
Left: a traction lift with a machine room on top of the shaft. The machine and controller are in the room, and the ropes drop through the floor to the car and the counterweight.
Right: a machine room-less lift. There is no room above the shaft. A compact machine is fixed in the headroom at the top of the shaft, the ropes run around pulleys on the car and counterweight, and the controller is in a cabinet beside the landing doors at the top floor.
Everything else is familiar. The car still hangs from ropes or belts, a counterweight still balances it, and the same safety systems protect it: the governor, the safety gear, the buffers and the door interlocks. Our lesson on how a traction lift works explains those basics.
Where everything goes.
| Equipment | With a machine room | Machine room-less |
|---|---|---|
| Machine | In the machine room | In the shaft, usually in the headroom on the guide rails or a bracket |
| Controller and drive | In the machine room | In a cabinet at a landing, often the top floor, or built into a door frame |
| Overspeed governor | In the machine room | In the shaft |
| Emergency and rescue controls | In the machine room | On a locked panel outside the shaft, usually at a landing |
| Roping | Often 1:1 | Often 2:1, so a compact machine can do the work |
The design depends on the manufacturer, so two MRL lifts can look quite different inside. Some fix the machine to the car guide rails, which carry its load down to the pit. Others mount it on a bracket or beam fixed to the shaft wall.
What makes an MRL lift possible is the compact gearless machine: a slim, slow-turning motor with the sheave mounted on it. Combined with 2:1 roping, it can lift the car without needing the space a geared machine would.
Why MRL lifts are so common.
The design is relatively recent. KONE says it introduced the world’s first machine room-less lift, the MonoSpace, in 1996, and other manufacturers followed with their own designs.
For new buildings, leaving out the machine room saves space and construction, and it removes a structure from the roof, which architects and planners often prefer. The efficient gearless machines that MRL lifts use also tend to consume less energy than the geared machines found on older lifts.
As a result, MRL designs are now a standard choice for new low-rise and mid-rise passenger lifts. Lifts with machine rooms are still installed, especially for higher speeds, heavy loads and taller buildings, and many existing buildings keep them.
Maintenance and rescue on an MRL lift.
Without a machine room, engineers reach the equipment from three places: the car roof, the pit and the landing cabinet. That changes how work is planned.
- Car roof: the machine, governor and top of the shaft are reached from the roof of the car, using the inspection controls to move it slowly.
- Pit: the buffers, the governor tension pulley and the lower part of the shaft are reached from the pit.
- Landing cabinet: the controller, the drive and the emergency and test controls sit behind a locked panel at a landing.
Working inside the shaft means working near moving equipment, often at height. Every job needs a safe system of work: isolating the lift, protecting the open landing, and controlling the car from a safe position. BS 7255, the UK code of practice for safe working on lifts, sets out how this should be done.
Rescue works differently too. On a lift with a machine room, an engineer can watch the machine while moving the car. On an MRL lift built to BS EN 81-20, the emergency and test controls are on a locked panel outside the shaft that only authorised people can open. It shows which way the car is moving, how fast, and when it reaches a floor where the doors can be opened, and it has an intercom to the car. It is not for building staff to use.
Safety first
Never open lift doors with a release key, enter a lift shaft or pit, or try to free trapped passengers unless you are trained and authorised to do so. If someone is trapped, use the alarm or call your maintenance provider. If anyone is in danger, call 999.
Replacing an older lift with an MRL lift.
When a lift with a machine room reaches the end of its life, replacing it with an MRL lift is often an option. The machine room can then be cleared and used for something else, and the building gains a lift with modern safety features and drives.
Whether it works depends on the existing shaft. The new lift has to fit the shaft’s width and depth, and it needs enough headroom above the top floor and a deep enough pit below the bottom floor. The guide rails or brackets that carry the machine also need a structure strong enough to take the loads.
Where an existing shaft cannot fully meet the standard for new lifts, BS EN 81-21 sets out alternative measures that can make a new lift safe in an existing building, for example where the headroom or pit is reduced. A survey of the shaft is always the first step.
Our lift modernisation page explains how we approach upgrades and replacements.
Engineer’s note
Before choosing an MRL replacement, ask how the equipment will be reached for maintenance and rescue in your building. A design that works on paper can be awkward in practice if the landing cabinet is in a busy lobby or the car roof is hard to access.
Check your understanding.
Three quick questions on this lesson. Choose an answer to check it, or open the answer below each question.
-
Where is the machine on a typical MRL lift?
Show the answer
B. Inside the shaft, usually in the headroom at the top. On most MRL lifts a compact gearless machine is fixed at the top of the shaft, on the guide rails or a bracket. The controller is in a cabinet at a landing.
-
Why do many MRL lifts use 2:1 roping?
Show the answer
A. It halves the load on each fall of rope, so the machine can be smaller. With 2:1 roping the load is shared between twice as many falls of rope and the machine turns faster, so a compact machine that fits in the shaft can lift the car.
-
Who can use the emergency controls on an MRL lift?
Show the answer
B. Only trained and authorised people. The landing panel gives access to the controller and to rescue functions. Only trained, authorised people should ever open it or use it.
Sources.
The primary sources for this lesson. We checked them when the lesson was last updated on 18 October 2026. How we research and check our lessons.
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Related reading
Thinking about replacing a lift with an MRL lift?
Talk to an engineer about whether your shaft, headroom and pit will take one.
Common questions.
Quick answers to common questions about this topic.
What is an MRL lift?
MRL stands for machine room-less. It is a traction lift with a compact machine inside the shaft, usually at the top, and the controller in a cabinet at a landing, so the building does not need a separate machine room.
Are MRL lifts harder to maintain?
Not harder, but different. The machine and other equipment are reached from the car roof, the pit or a landing panel rather than a machine room, so engineers need the right training, access and safe systems of work for each lift.
Can an old lift with a machine room be replaced with an MRL lift?
Often, yes. The new lift has to fit the existing shaft, headroom and pit, and the structure has to take the loads on the guide rails or brackets. A survey shows whether an MRL lift will fit, and the old machine room can then be freed for other uses.
Do hydraulic lifts need a machine room?
Hydraulic lifts need space for the pump unit and its controls, usually in a small room or cabinet close to the shaft. That space is often called a machine room or pump room, even though it can be much smaller than a traction machine room.