How to identify the correct window lock before buying

HOW TO IDENTIFY THE CORRECT WINDOW LOCK BEFORE BUYING

To correctly purchase the right window lock replacement we first need to identify which lock you need, and in order to do that we need to remove the lock.

If your window has broken in the locked position you may need a handyman to bypass the lock to open the window or if you are feeling lucky you can try it yourself.

Top tip: open an identical window and remove the lock to identify if you need to purchase a new lock ready before changing the broken lock.

BRANDING.

Many lock brands will stamp their name or logo on the face of the lock, this is your first task to find and identify this.

Common brands are as follows:

• Avocet
• GU
• Maco
• Mila
• Nico
• Saracen

INSERT BRANG LOGO IMAGE HERE

After we know the brand the next thing we need to do is measure the entire length and also the backset

The next job is to take note of the faceplate style and central gearbox style

Older window locks used a system called “U” rail to use on windows prior to when pvcu window manufacturers introduced the standadised “eurogroove” system

The profile of the faceplate would look like a flattened letter U in many cases.

The gearbox on these older window locks would be thin and offset in relation to the faceplate

Backset, this is a measurement taken from the face of the lock to the centre of where the square spindle bar goes through the lock, this measurement can be any of the below and is sometimes stamped on the side of the gearbox

• 20mm
• 22mm
• 25mm

If you think your window lock could be of this older style we would highly advise taking some photographs and emailing them to us on sales@sash-hardware.co.uk

INSERT U RAIL AND OFFSET GEARBOX PICS HERE

If your window is using the standadised eurogroove system then this makes things easier.

So you know the brand, you know the length and you know the backset, just one final thing the measure.

CAM height, those sliding parts that do the locking come in three main heights

• 7.7mm
• 9mm
• 10.5mm

With the 7.7mm being the much more common.

Can’t find your exact match? Lets say you have a discontinued GU window lock, it measures 800mm in total length with a backset of 22mm and cam height of 7.7mm, it is very possible and often done to fit an alternative lock that matches these dimensions, such as a Maco 800mm with a 22mm backset and a cam height of 7.7mm, it is also very possible to fit a lock smaller or longer in total length if the window allows, what you cannot normally change is the backset, if your lock is a 22mm backset you need to fit a lock with a 22mm backet as the holes drilled for the handle determines this and cannot be changed.

The only issue is you may need to move the keeps attached to the frame to suit the new lock.

The history of window locks in the pvcu industry is vast and ever changing therefore this guide cannot possibly be a concise for each type certainly without being it being 25 pages long, if you are unsure we would be more than happy to help to identify your lock, simply take 4 or 5 images of the lock looking at it from different angles and side, with it out of the window and email them along with as much descriptive information from this guide to sales@sash-hardware.co.uk