Article updated: 07-07-2026
What is an elevator pit?
The pit is him space excavated or built under the threshold of the last elevator stop. Its floor must be smooth, substantially horizontal and with sufficient load-bearing capacity to withstand the forces transmitted by the stops or shock absorbers.
In installations where the level of the pit is below street level or in areas with risk of infiltration, it is mandatory to waterproof it to avoid the accumulation of water, which could damage the electrical and hydraulic components housed in that space.
What is it for?
The pit fulfills several simultaneous functions:
- It houses the shock absorbers or limit switches, which stop the descent of the cabin in the event of failure of the automatic stopping mechanisms, or the electric limit switches. In electric elevators, they also act as a safety element in the event of cable breakage.
- Allows maintenance personnel to work safely when it is necessary to intervene in the lower part of the cabin or in the components located in that space.
- Provides safety tour necessary so that, with the cabin supported on the shock absorbers, there is enough space to protect a person.
- In hydraulic elevators, the pit it can partially house the cylinder or piston in submerged type installations.
What measurements should an elevator pit have?
The depth of the pit must be sufficient so that when the cabin is on the fully compressed shock absorbers, there is still free space of a height equal to or greater than 0.5 m, sufficient to allow a person to remain safe in the space available under the cabin.
The UNE-EN 81 Regulation is more precise and contemplates that there must be a space to house a straight parallelepiped measuring 0.5 x 0.6 x 1 m that rests on one of its faces.
In the freight elevator , in the event that due to the dimensions of the enclosure there is not enough space to accommodate a person under the above conditions, an emergency stop device (it may be a switch) and a power outlet must be installed in the pit:
- The switch located inside the pit and next to the access door, so that it can be operated from outside, will cut off the general series of doors and keep the elevator stopped until it is operated in the opposite direction. To avoid errors, the stop position must be marked with a stop sign.
- An electrical outlet to plug in a lamp or portable tool.
| Parameter | Minimum value (UNE-EN 81-20) |
| Free space in pit (with cabin on shock absorbers) | 0,5×0,6×1 m |
| Free width in pit for safe work | ≥ 0.5 m measured from the cabin projection |
| Pit floor resistance | Enough for static load + shock absorbers |
Mandatory equipment
Regardless of the depth, the regulations require that they be installed inside the pit:
- Emergency stop switch, located next to the access door and operable from the inside. You must cut off the general series of maneuvers and keep the elevator stopped until it is manually deactivated. It must be marked with the indication «STOP» in the stop position.
- Electrical outlet (at least a 230 V plug), to be able to connect portable lamps or tools during maintenance tasks.
- Permanent lighting of the pit, accessible from the outside before descending.
- In pits with a depth greater than 1.30 m, fixed access staircase, located outside the cabin clearance.
In forklift-type installations where the dimensions of the enclosure do not allow free space for a person in the previous conditions, these devices are even more critical, since they constitute the only safety measure available for the operator who must intervene in that space.
How to safely access a pit
Access to the pit can be achieved by two procedures:
- Through a special opening in the enclosure, the solid-metal door must open outwards and be equipped with an effective lock that allows it to be locked from the outside without a key by pressing it, and opened from the inside without a key. It must also have a switch embedded in the control power supply that will prevent the elevator from operating when the door is open.
- For the lowest access door to the premises, in which case it will be equipped with an interlock that prevents it from closing, if the cabin is not in front of it.
- When the depth of the pit, from the threshold of the access door, exceeds 1.30 m, a ladder must be installed outside the pit clearance to allow the elevator maintenance personnel a comfortable and safe descent to the pit floor level.
Reduced pit: is it possible?
In installations in existing buildings where civil works are limited, there are technical solutions which allow the minimum depth of the pit to be reduced, especially in hydraulic elevators. Some specific power plants and damping systems are approved to work with shallow pits (from 0.10-0.20 m in special solutions), provided that the manufacturer provides technical documentation that justifies compliance with safety requirements. equivalents required by the standard.
If you have a project with space restrictions in the pit, at GMV we can advise you on the most appropriate solutions for each case.
Literature
Miravete, A., & Larrodé, E. Elevators: Principles and innovations. Reverté Editorial. See Editorial Reverté
AENOR. UNE-EN 81-20:2020. Safety rules for the construction and installation of elevators. Part 20: Elevators for people and people and loads.File in AENOR store
Ministry of Industry. Royal Decree 355/2024, of April 2, ITC AEM 1 «Elevators».BOE-A-2024-7258
Is the current standard. The cables and relays are replaced by one or more electronic boards integrated with microprocessors, very similar to those of a current computer.
7 Responses
You say, referring to the pit: "... The UNE-EN 81 Regulation is more precise and states that there must be a space to accommodate a straight parallelepiped of 0.5 x 0.6 x 0.8 m that rests on one of its faces..."
Are these dimensions not those corresponding to the upper space, inversely to the pit?:
«… there must be sufficient space above the cabin to contain a rectangular parallelepiped not less than 0.50 m x 0.60 m x 0.80 m resting on one of its faces…»
While the corresponding dimensions of the pit are:
"... there must be sufficient space in the pit to accommodate at least a rectangular parallelepiped measuring 0.50 m x 0.60 m x 1.0 m resting on one of its faces..."
Hello, I would like to know if it is worth installing a basic elevator with a capacity for 4 people. I would like to put it in a three-story building, the space is already made. If you can give me more or less advice on how the hydraulic and electric ones would work. Thank you very much and I look forward to your response.
Hello, I would like to know what type of elevator for the disabled (electromechanical or hydraulic) is required to move vertically from a continental or dry area to a floating platform (average level difference of 3.75 meters). I would also like to know the general characteristics of the elevator and the shaft. I await your response. Thank you.
I have a space for an elevator measuring 170 wide by 117 long or deep. The pit under the cabin measures 117x130x130. Is this valid?