Are all forms of T handle inherently insecure, or is only the key lock fitted within the core of a T handle the insecure part? If a lock body is used that uses a T handle alongside a euro lock (see example image below), is this any different to a lever handle being used? Or, is the leverage afforded to the T handle design the weak point, regardless of the lock type used alongside?
I am looking to upgrade an existing T handle lock with dual side spring loaded catch slam locks to a considerably more secure locking solution. The existing door is hinged at the top, similar to a truck canopy, and is manufactured from a 38 mm thick GRP and plywood composite panel.
If required (almost certainly will be), I am able to fabricate metal bracketry and GRP to suit a lock body and ancillary mechanisms.
I would like to upgrade this to a considerably more secure option, ideally using a lock body with a high security anti-snap keyed euro cylinder and internal thumb turn, or similar.
I have in mind to use a centre roller shutter lock (i.e. https://www.viro.it/en-gb/hardware/roller-shutter-locks/18270-series-with-security-escutcheon-and-suitable-for-profile-cylinders) with an external fixed rigid handle to pull open the door. However, I am hesitant whether the key would risk snapping inside of the lock when pulling back the existing spring loaded catch slam locks?
Are there roller bolt catches which could replace the existing slam locks? This would allow the door to catch when pulled down but not put strain on the key when locking/unlocking?
Alternatively, could I have some suggestion for other locking options which may be more appropriate and offer a high level of security?
