What is the difference between an espagnolette and a cockspur window handle?

Almost every uPVC casement window in Britain uses one of these two systems, and they are not interchangeable. Knowing which you have takes one look at the handle, and it decides everything about what you order and whether handing matters.

Step by step

1. Look at the handle itself.If the handle has a curved metal claw or hook on the underside that swings round to grip a block on the frame, it is a cockspur. If the handle is a plain lever with a square spindle disappearing into the sash, it is an espagnolette handle driving a lock strip.
2. Look at where it locks.A cockspur locks in one place: at the handle. An espagnolette drives a strip with cams or mushrooms along the whole sash edge, locking at several points. That is the practical difference and it is a real security difference.
3. Measure a cockspur correctly.Two things: the handing, and the 'nose height' or step — the distance the hook is offset from the handle plate, which must match the projection of the wedge block on the frame. Common steps are around 9mm and 21mm, and a wrong step will not reach or will not close.
4. Establish the handing on a cockspur.Cockspur handles are made left-handed and right-handed and cannot be reversed. Describe it in plain words — 'the hook swings towards the hinge side, which is on my left as I look at the window from inside' — as well as by any code.
5. Measure an espagnolette handle correctly.The spindle length, from the underside of the handle plate to the tip, and whether it is 8mm or 7mm square. The screw centres on the plate, commonly 43mm. And whether it is inline or has a cranked plate. Handing usually does not matter because the plate is symmetrical and the spindle drives either way.
6. Check the height of the spindle for a lock strip replacement.If the espagnolette lock strip itself is being replaced rather than the handle, you also need the distance from the end of the strip to the centre of the spindle hole, plus the overall strip length and the cam positions.
7. Decide whether to upgrade a cockspur.Cockspur handles can be replaced with locking versions that take a key, which is worth doing on a ground floor window. Converting a cockspur window to a full espagnolette system means routing the sash for a lock strip and fitting keeps, which is a job for a window repairer rather than an afternoon.
8. Check the lock and the key on either type.Both come in locking and non-locking versions. On a window that is on an escape route, think about whether the key is reachable and where it lives, because a locked window with no key to hand is a genuine hazard.

Alternatives

• Cockspur handle: Single-point, hook grips a frame wedge. Older uPVC and aluminium windows. Cheap and simple, handed, and the step dimension has to match.
• Espagnolette handle: Drives a multi-point lock strip inside the sash. The standard on modern uPVC casements. More secure, and measured by spindle rather than handing.
• Tilt and turn handle: A different system again, turning through three positions to drive a perimeter mechanism. Not interchangeable with either of the above.
• Window restrictor or limiter: Fitted alongside either handle type where a window needs to be stopped from opening fully. Its own subject, and often required above ground floor.

Questions people ask