A door closer is a mechanical device that automatically and steadily pulls a door back into its frame after it has been opened. It consists of a metal housing containing a spring and a hydraulic damper, and is fitted to fire-rated, sound-rated and self-closing doors.
How it works
Opening the door tensions the spring inside the closer. When the door is released, the spring pulls it shut. A hydraulic oil damper controls both the closing speed and the latching action so that the door:
- Does not close too slowly (which would undermine the fire-rated performance)
- Does not slam hard against the frame
- Has a final “snap” that drives the latch into the strike plate
Most closers have two or three adjustment screws for speed, latch speed and (sometimes) back-check or delayed action.
Where they are required
Door closers are commonly required — or strongly advised — on:
- Fire and smoke doors — mandatory under most building regulations to keep compartmentation intact
- Escape doors — so they self-close after use
- Toilet doors in public buildings — for privacy and hygiene
- Draught lobbies and main entrances — to limit heat loss and draughts
- Hotel rooms and flats — for acoustic separation between spaces
Types of door closer
| Type | Mounting | Application |
|---|---|---|
| Overhead closer | On the door or frame at the top | Standard, visible |
| Concealed closer | Fully mortised into the door or frame | Architectural / aesthetic projects |
| Floor spring | In a casing under the door | Glass entrance doors, double-acting doors |
| Free-swing closer | With electromagnetic clutch | Held open until the fire alarm releases |
Closing force (EN 1154)
The standard EN 1154 grades closers into seven force categories (EN 1 to EN 7), based on door width and weight. A normal internal door (up to 950 mm wide) typically needs an EN 3 closer; a heavy external door may need EN 6 or EN 7.
Maintenance
A door closer is almost maintenance-free, but a few pointers:
- Never force the closer open with a wedge — this will damage the hydraulics
- If the door closes unevenly, fine-tune the adjustment screws a quarter-turn at a time
- If oil leaks or the arm loosens, replace the unit
Related terms
- Hardware
- Fire resistance
- Fire compartment
- Door
- Hinge
- Door buffer
Want to learn more about construction terms? Visit the knowledge base at Fred’s DIY Plans.