Replacing a five-lever lock
Five-lever locks are used for entrance, and back doors – five levers approved to BS3621 is the minimum requirement for entrance doors. Mortice lever-locks can have between 2 and 7 levers. The more levers there are, the more difficult the lock is to pick. Fitting a mortice lock from new requires drilling into the edge of the door in order to accommodate the lock (using a similar technique to that shown for fitting a latch in the guide ‘Fitting internal doors’). However, if you are simply changing a lock, it is a very straightforward process to take out the old one before inserting a replacement.
|1. Remove the handle on the inside of the door by undoing the retaining screws. Place the handle to one side to reattach later.|
|2. Remove the spindle bar that fits through the back of the lock and into both handles. Again put it to one side as this will be reinserted.|
|3. On the edge of the door, remove the screws that secure the lock. You may need to thread a screwdriver through the spindle hole and pull towards you to release the lock from the door edge.|
|4. Fit and screw the replacement lock in position. If necessary chisel out a little more wood from the door edge to ensure that the lock fits snugly.|
|5. Reposition the spindle and inside handle. Check that the new lock works smoothly and engages correctly with the strike plate on the door frame.|
Because most lever locks are of a standard size, the fitting procedure is normally very simple. However, before buying a new lock check the size of the new one with the important measurement being how far back from the front edge of the lock the spindle and keyhole are positioned. Look for measurements relating to ‘backset’ and match with your existing door lock.