We offer UPVC mechanism repairs and replacement

UPVC Door Repair

uPVC Door Repair Specialists

uPVC door locks may become faulty due to several issues – luckily many of which can be fixed without needing a whole new door. Our highly trained engineers carry all the common gearboxes necessary to carry out UPVC doors repairs for the local area of Stirling.

upvc door repair mechanism from door in stirling

Measuring a uPVC gearbox

On many locking mechanisms, it is possible to change just the centre gearbox instead of the whole strip. We are often able to fix this on the first visit as our mobile locksmith in Stirling is fully stocked with all the common gearboxes for your uPVC or composite door. This means you will save on the cost of a full strip and labour on a return visit, getting value for service for your uPVC door repair in Stirling.

We have gearboxes available to replace Mila, Cego, Surelock, Fuhr, Yale, Fullex and Maco, GU, Era, and Saracen.

When identifying a gearbox for a uPVC door the first measurements to take into account are the centre (often called PZ), and the backset.

Measurement A is known as the centre. This is the distance between the centre of the barrel and the centre of the spindle.

Measurement B is the backset which is the distance from the front of the locking system to the middle of the spindle. The most common are 28mm, 35mm and 45mm. There are some other sizes on older door sections of uPVC doors.

Check if there is a manufacturer name stamped anywhere on the strip.

image showing how to measure upvc door repair gearbox in Stirling

uPVC and composite doors require a minimum of three points of locking for insurance purposes. This can be attained with either hooks rollers anti-slip bars, bolts, or a mixture of the different styles. All of which are found on the doors of Stirlingshire homes.

There are various points on the door which must marry up with the frame for the lock to be fully engaged. If the door is slightly out of alignment, it can cause an unnecessary strain on the lock when being closed. Over time this can cause gross failures of the moving parts inside the mechanism. However, this can often be rectified and realigned by one of our uPVC door engineers in Stirling.

Unsure who has a key for your house? If you require a free security review on your door lock, you can give Bob’s Locks a call today and we will be happy to talk through the different options.

Bob’s Locks can open jammed doors and get your stiff uPVC door lock working like new. As the #1 locksmith in Stirling, Bob’s Locks stock a vast array of uPVC door lock parts that enables us to carry out repairs on 95% of all failed uPVC gearboxes on the first visit, giving you both peace of mind and great value with just 1-hour chargeable labour.

uPVC door lock issues? Have you lost your keys, door failed, or has become stiff?

Give Bob’s Locks a call today and your local Stirling locksmiths will be happy to discuss the options with you. Or call into the shop at 17 Upper Craigs, Stirling.

Save your money with our uPVC specialists in Bridge of Allan, Stirling, and Dunblane.


This can be solved. We have various options available to adjust the door height and position, sometimes we may need to rehang the door or toe and heel the insert.

This is a common occurrence. We carry all sizes of British standard cylinders with the ability to make all doors in your property work using one key.

The gearbox can often fail due to other issues within the door and frame. Once we have replaced the faulty part in your uPVC door, we will realign your door to work like new again.

This is often a sign of a blockage in the gearbox or a spun cam due to having used extra force. It can also happen after having tried to use the lock when a key was in the other side. We can repair this issue in one visit and fit a new cylinder with a lifetime guarantee. 

This often arises when the door is out of alignment. You should get your uPVC door fixed at this stage to save expensive bills down the line. We can fix uPVC doors with adjustments, taking the strain off the working part of the door and leaving it fully functional again.

This indicates the gearbox has failed and will require a replacement and an adjustment to the door.

This indicates the mechanism may have failed and may require a replacement and door adjusted to suit.

We can help. We provide free security reviews and can help make your home secure again giving you peace of mind on your home security once more.

Looking for a UPVC specialist in Stirling that you can trust?