Transom Spring Units

What is a Transom Spring?

Transom spring units are hydraulic units fitted in the door frame to aid door closing on more industrial and commercial use doors.

Not all locations are suitable for floor spring units due to under floor pipe work, flooring materials and the depth of floor available, in this occasion a transom spring unit would be most suitable option.

  • Transom spring units are more commonly found on shop fronts, as they are predominantly fitted within a purpose made section of an aluminium or steel frame.
  • Transom springs can be fitted into a timber purpose made frame but the size will need to be taken into consideration.

How do I know which type to buy?

Listed below are the main factors that have to be taken into consideration when purchasing transom spring units. Please click on the links below for more information.

Door Weight and Width
There are various transom spring units available. All manufacturers will have a maximum door width and weight for each of their products. This is usually determined by the different strengths of the models.
Traffic Flow
A door which gets a lot of use i.e. Main Entrance Door to a Restaurant, may require a more heavy transom unit than an internal office door.
Door Location
Internal Doors - Some internal doors have specific needs i.e. are required to swing both ways (double action) as in kitchen doors. External Doors – These may need to be closed for security, with the option of being held open i.e. when deliveries are being bought into the building. Fire Doors – These doors need be in a closed position in the event of a fire, therefore specific non-hold open floor spring units only can be fitted.
Fire Doors
Fire doors must not be fitted with a hold open transom spring unit.
The cost can vary enormously between strength of units and manufacturers. As a general rule as long as the above considerations are taken into account you should get a suitable product for your location
Additional Door Parts
To fit a transom spring unit to a door, you will require additional parts fitted to the door and at the bottom of the frame. These parts include various different drive arm assemblies and bottom bearing assemblies. Please note there are many different types of these parts dependant on the make of unit, existing door parts and type of door.
DDA Regulations
The Disability Discrimination Act regulations came into force in October 2004. You must ensure your doors cover the necessary requirements for your location when you fit any form of door closing equipment to your door.
Back Check
You may need to choose a closure with back check. This creates a buffer to stop the door being pushed back hard against the wall. This prevents damage to the door, transom, handles etc. this can also be useful in an area where the wind can blow a door open hard.
Latching Action
A location may require the door to latch onto a security lock or magnet, therefore a transom spring unit with adjustable latching action would be required to set the door correctly.