For vulnerable flat doors, specially shaped metal strips are available for adding to the strength of a door. These run from the top to the bottom of the door and also reinforce the frame.

Replace standard glass back door panels that could be at risk with laminated glass that is virtually impossible to smash.

Tip: The door will only be as good as its frame - replace it or repair it if it is rotten or loose.

French Windows and Patio Doors
French windows can be a weak point because their frames are often too thin to fit a mortise lock.

Start by adding flush-fitting rack bolts that lock into the top and bottom of the frame. Before buying a central lock, check that it can be used on outward-opening doors. In high risk areas, it may be worth adding foldaway metal security grilles as well.

Upgrade metal-framed patio doors with surface-mounted locks to stop burglars prising the sliding glass sections out of the rails.

Extra Precautions
If you have just moved into a house, it's worth changing the locks on all the exterior doors so you know exactly who has keys for your home (see Secure It for more tips.) You can save money by just replacing the cylinder of a rim lock.

Contact your CPO (Crime Prevention Officer) through your local police station for extra advice on home security, and ask if there is a local Neighbourhood Watch scheme you can join. For more information, log on to the Master Locksmiths Association.