How to Improve Security on Your Back Door

Your back door sits out of sight of the street, often sheltered by a fence or a hedge, and unlike the front door it rarely gets a second glance. That combination makes it a favourite entry point for opportunist intruders. The good news is that you do not need to spend a fortune to make it a much harder target — a handful of well-chosen upgrades, most of which can be fitted in an afternoon, will send most casual burglars looking for an easier house.

Start with the lock cylinder

The cylinder is the small metal barrel in the middle of the handle that your key turns. On many older uPVC doors it is the weakest point in the whole assembly, and it is the part that experienced thieves know how to attack. Three techniques are common: snapping, where the cylinder is broken off where it protrudes from the door; bumping, using a specially cut key and a sharp knock; and straightforward picking or drilling.

Replacing an ageing cylinder with a British Standard Kitemark TS007 three-star cylinder — or a one-star cylinder paired with a suited security handle — defends against all three. Look for the BSI Kitemark and a Sold Secure stamp on the packaging. When fitting, make sure the cylinder sits flush with the handle backplate, or protrudes no more than a few millimetres. A cylinder that sticks out is a cylinder that can be gripped and snapped.

It is also worth checking whether your door carries a PAS 24 rating, the recognised standard for enhanced security performance on doorsets. If it does not, a replacement door may be a better long-term investment than layering upgrades onto something worn out.

Add a security chain or a door limiter

A chain is a cheap extra layer that stops the door being pulled wide open the moment you turn the handle. Two practical details separate a chain that works from one that does not:

• Fix it with long screws — 75mm or more — that reach into the frame or the wall behind, not just the plastic or timber trim. Short screws pull out under a hard shove.
• Choose a chain with a solid, riveted body and plenty of metal, and mount it at a comfortable eye height.

A door limiter does the same job more robustly. It allows the door to open a few inches for a delivery or a conversation but holds firm against force. Pair either option with a wide-angle viewer or a small glazed panel so you can see who is there before opening anything at all.

Check the hinges — and add hinge bolts

On an outward-opening door, the hinges are exposed, and that is exactly where a determined intruder will start. Hinges should have at least two or three solid fixings into both the frame and the door leaf, with proper steel screws rather than the short ones often supplied. If the hinge pins can be knocked out, the door can be lifted clean out of its frame.

Even on inward-opening doors, hinge bolts are worth adding. These are tapered metal bolts fitted to the opening edge of the door that slot into receivers in the frame, preventing the door being levered away on the hinge side. Many modern uPVC doors have "dog bolts" built in — small spring-loaded pins at the top and bottom corners — so check what you already have before buying anything extra.

Glass, frames and the door itself

Roughly two-thirds of a uPVC door is glazing, and a single pane of ordinary glass is easy to break quietly. Consider the following:

• Laminated glass rather than toughened glass for the panel nearest the handle. Laminated glass holds together when broken, so a hole cannot be cleared quickly.
• Security film applied to the inside face, if you would rather not replace the pane.
• Internally beaded glazing, where the beads sit on the inside of the door and cannot be prised off from the garden.

Then check the frame itself: no soft or spongy patches, no gaps where it meets the wall, and no gap at the threshold wide enough for a bar to get purchase. If your door has a letterbox or a cat flap, keep it well away from the lock and handle.

Lighting, habits and the wider garden

Locks only work if they are used. Turn the key every time, even when you are just popping out to the bins or bringing in the washing. Keep keys out of reach of any glazing rather than on a hook beside the door, and give a spare to a neighbour instead of hiding one under a plant pot.

Outside, a motion-sensor light above the back door costs very little and removes the cover of darkness. Keep side gates shut and locked, trim back shrubs that screen the doorway, and use a timer or smart plug to switch on a light inside on winter evenings so the house never looks empty. If you have an alarm, set the back door zone to chime.

None of these steps is expensive on its own, and most take minutes rather than hours. Do the cylinder first, add the chain or limiter, check your hinges — and you will have closed off the routes that opportunist thieves rely on most.