Door and window security

The majority of burglaries are the result of thieves gaining entry through open or unlocked doors and windows.  Locks are only effective if they are used.  Keep your doors and windows locked, even if you are elsewhere in the house.


Wooden doors

  • Ensure that the frame is firmly fixed to the wall and in good condition.
  • Fit internally beaded and laminated glass to a minimum specification of BS EN 356 P1A.
  • Solid core doors offer much more security than panelled designs. If your door has thin or weak panels, consider re-enforcing them.
  • For doors that are your main or sole fire escape, consider thumb-turn deadlocks.
  • We do not recommend using a door chain as a means of security.

As well as the above:

For front doors

  • Use a five-lever mortice sash lock or rim lock (night latch) manufactured to BS3621.  Fit it one-third from the top of your door AND a mortice deadlock one-third from the bottom of your door.
  • Add a security deflector, manufactured to TS008 (door mounted), to your letter box to prevent someone reaching in.
  • Consider installing a door viewer if you cannot see who is at the door. If the light is poor, consider fitting a dusk till dawn bulkhead light next to your door.

For rear doors

  • Install mortice security bolts approximately 50-150mm from the top and bottom rail.
  • Fit a BS 3621 five-lever mortice sash lock just below the middle of the door.
  • Pet flaps weaken doors. Larger ones also allow a burglar to climb through them! We recommend that such devices are not used.

UPVC and composite doors

  • Many older UPVC doors have weak locking mechanisms and are not very secure. 
  • Always lift the handle and turn the key to ensure the door is locked!
  • We recommend cylinders manufactured to either BS: TS007 (3 star) or SS312 Diamond. These cylinders are not easy for thieves to break.  They improve the security of a door even if the door furniture is not security rated.
  •  If you are replacing the cylinders yourself, always ensure that the external part of the cylinder does not protrude more than 3mm beyond the door furniture.

French and outward opening doors

  • Fit a BS 3621 five-lever mortice sash lock just below the middle of the door.
  • Fit wooden French doors with mortice rack bolts to the top and bottom of each door leaf. You can use surface mounted locks as an alternative. 
  • Seek the advice of the manufacturer and a reputable locksmith before fitting extra locks to a UPVC unit.
  • Fit hinge protectors or hinge bolts (sometimes called “Dog Bolts”) to each door hinge.
  • Consider installing laminated security glass to standard BS EN 356 P1A or greater, to vulnerable doors.
  • If your property is especially vulnerable or isolated, consider installing retractable internal grilles.  Use ones manufactured to LPS1175 SR1 as a minimum.

Sliding patio doors

Older sliding patio doors can be vulnerable and easy to remove.

A timber batten fixed into the top track of the door frame can help limit the opportunity to simply lift the door out of the frame.

Specifically designed patio door locks fitted onto the frame or stile of the fixed glazed unit or the door will also help improve security

It is important to install such locks exactly to the manufacturer’s instructions. If fitted in different locations they may not work! We always recommend using a reputable locksmith for such work.

Replacement doors

We only recommend installing door sets manufactured PAS24-2012 for domestic properties.  PAS24-2012 door sets are manufactured to a standard that will keep a well-equipped and determined burglar out of your home for at least 3 minutes. Whilst this may not sound like a long time, consider that the average burglary lasts less than 1 minute!


Regardless of whether your windows are plastic or wooden, casement or sash, the same security principles apply. Here are our recommendations:

  • Replace rotten window frames using items manufactured to BS PAS24 -2012.
  • Check that the glazing is secure. If the putty or bonding is old and split, it’s easier for a burglar to remove the glazing.
  • Check external beading. If it is loose or not securely fixed, it can be easy for a burglar to remove.
  • Use frame locks if you only have a single lock point. If your windows only have a single latch, fit frame locks to the top and bottom third of the opening side of casement windows and to each side of an sliding sash window.
  • You can fit sash windows with specialist screw locks and sash stops.
  • Use extra frame locks if your UPVC window does not have side bolts. Older UPVC windows are not very secure even though they appear to lock in several places. There are several designs of frame lock that you can use with UPVC windows but take care when installing them.

Security glazing

Windows in secluded or vulnerable areas or where high value items such as jewellery and antiques are present can be additionally secured using laminated security glass.

  • The minimum recommended standard for general domestic use is a laminated glass manufactured to BS EN 356 P1A
  • Higher ratings available dependent upon your security requirements.
  • If you are considering security glazing, we recommend that you replace the complete window with one manufactured to BS:PAS 24-2012, using laminated security glass.
  • If the unit is a double glazed sealed item, we suggest that you specify laminated glass on the inner pane as a minimum.

Replacement windows

For general domestic security, use windows manufactured to BS: PAS24-2012. These windows have a guaranteed security performance rating and are manufactured in a variety of materials. Specifying PAS24-2012 takes the guesswork out of picking the right specification of locks, glazing and frame.  These units are tested as a whole and not as individual components.

We recommend that you use laminated security glass manufactured to a minimum of BS EN 356 P1A for all ground floor windows and those windows on the 1st floor of higher that are vulnerable (such as those adjacent to a flat roof).

Security grilles and shutters

For general domestic property security use retractable internal grilles manufactured to LPS 1175 SR1 or greater.

Grilles add a further level of security to your home but consider them only where your security risks are higher than average.  For instance where:

  • the property is empty for long periods
  • the property is isolated
  • the property contains valuable items
  • a particular window, patio door or French door is especially vulnerable due to its location.

Fire safety

NEVER use a keyed frame lock on windows that you would use as your intended fire escape. There are many designs of keyless lock that can be opened by pressing a button.

If you lock your windows using the handle, keep the key out of sight but in a place that is close by. Make sure that EVERYONE in your house knows about the location and that EVERYONE can reach it.

If you have difficulty using keys or are less dexterous, there are a variety of items you can fit in place of the more common-place locks. Speak to a Master Locksmith Association ( member about what is right for you.

Choosing an installer

We recommend that you use manufacturers and installers accredited by Secured by Design and locksmiths who are members of the Master Locksmiths Association. 

When selecting a product or installer with Secured By Design, check which of their products carry the accreditation.

Secured By Design

Master Locksmiths Association

Report it

If you have been a victim of a burglary, call 101 or report it online.

If a burglary is in progress and you are in immediate danger, call 999.

More help and support

For further advice or recommendations, contact our Crime Prevention Advisers

This contact is for crime prevention advice only.  Please do not use this email address to report crime.  Call 101, or 999 in an emergency.

24 May 21 2:27 PM

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