Position of Magnetic door retainer

[Guest Davidta]

Hi,

are there any guidances or legislations concerning the position of MDR in relationship with closing device? When designing door retainers to doors with floor mounted springs and high level closers, with say, regard to prevent door stresses and the fire door from warping so that the retainer should be mounted adajacent to the closer? Or would this be just best practice?

[Guest Ryan Mcmullan]

The DHF, code of practice: hardware for fire and escape doors, makes quite a substancial reference to the positioning of mag locks on timber doors, worth a read.

[Tom Sutton]

I am not aware of any guidance or standards regarding this aspect and certainly no legislation. The only standard I am aware of that deals with the device itself is BS EN 1155 :1997 but I cannot find anything relating to this aspect.

The usual term used is " Install in accordance with manufacturer's instructions " and I understand your concerns especially if you are a manufacturer. However as fire doors are usually well constructed, ridged and subject to other stresses, then this additional stress should be well within the capabilities of the door but I accept stress should be reduced as low as possible.

My only suggestion is that the door should not be kept under stress 24/7 and my advice was always to release the door, using the manual switch, to the closed position during sleeping hours. Followed by an inspection to ensure that all the fire doors held by magnetic hold open devices have worked correctly.

[Tom Sutton]

From the number one expert on fire doors and I consider the bible when discussing fire doors, "Best Practice Guide to Timber Fire Doors" states,

Avoidance of twist in door leaves It is important that the magnet is on the same level as the door closing device, thus when used with an overhead closer the magnet will be at door leaf head height and when used with a floor mounted closer it will be at ground level. The importance of the location of the hold-open device is to avoid the twisting force that would be applied to the door leaf if the holding point were not at the same level as the closing force. This force can permanently distort door leaves and the door leaves when distorted will not close fully or correctly.

Page 82 clause 20.28.4

[Guest fredgast]

We want to install the Dorgard fire door retainer. Is this not the same problem? Will they warp the door over time, as they are installed at the bottom and the door closer is at the top?

[Safelincs]

Hi

Dorgards are programmed to release every 7 days to avoid warping. In addition you might want to consider setting them for night time release. In that case they will close every night. This also helps to prevent any warping of the fire door.

If you have fire door prone to warping you might want to consider a free swing door closer that doe not apply any force on the door during normal operation.

Harry