How to install a rim deadlock

Rim deadlocks can be used to add an extra layer of security to a front door. It is absolutely possible to install two locks on the same door and doing so will only help to make your entrance safer. Rim locks are very straightforward to install, but you do need to ensure your fixings are well secured to ensure the lock performs as expected. Installing a deadlock on a timber door shouldn't pose any great problems as the material is easy to drill when it comes to securing the lock. However, if you have an aluminium or PVC door, installation will be trickier given the structure of the material and the narrow width of the door frame. You will have a limited choice of locks with these types of doors.

It's important to take great care when installing the strike plate as this is the part that will deal with the most force in the event of a break-in. When an intruder attempts to force the door from the outside, their aim is to knock the strike from the surface to which it is secured. That's why you need to think carefully about the quality of your surface and the placement of the strike plate before you install the deadlock.

Steps

1. Checking the condition of the lock and set it into position

2. Marking out your drill holes using a template

3. Securing a wooden block to the door

4. Drilling the cylinder hole

5. Fitting a lock without a cylinder guard

6. Fitting a lock with a cylinder guard

7. Fitting the lock strike plate

Checking the lock

Before you set about installing the deadlock you need to check that it works correctly and that all parts are accounted for. Additionally, you need to carefully read the instructions supplied with the product. Every type of deadlock and every brand will call for a slightly different installation. To help you position the lock and drill your holes, most brands will supply their locks with an installation template.

Positioning your deadlock

Before you mount the lock on the door, it's important to check that the lock won't weaken the door in any way in your chosen spot. It's also important to check that the strike plate is able to align properly. Some locks come with spacers for the strike. It's also possible to find more specialist locks designed for things like metal door frames or offset hinges.

• Place the drill template where you plan to install the deadlock.

• Attach it to the surface using tape.

• Pierce through the paper at the centre of each drill hole and mark the surface of the door with a pencil ensuring your marks are clearly visible.

• Remove the template.

Take a small plank of wood or wooden block and two clamps and fit the assembly over the surface where the cylinder will go on the outside of the door. Your block or plank needs to be bigger than the drill hole. If your lock comes with a cylinder guard, you need to make sure that the block covers the holes where it will be attached on the outside of the door.

This piece of wood will stop the wood splitting when the hole saw or drill bit pierces through the material. Secure the wooden block with the clamps. Be sure to cover up the clamping plates to ensure they do not mark the inside of your door (using another wood block, for example).

The diameter of your hole saw or drill bit must be slightly larger than the diameter of the cylinder. If the outside of your lock is fitted with security fittings (such as a cylinder guard) check the drilling diameter required for these parts.

You must drill the largest hole first and do so in one go. Place the pilot bit on the mark you drew earlier and drill the hole making sure to keep your drill straight. Drill at an even pace and do not go too fast, especially when you are reaching the end of the hole. This will help to prevent the wood from splitting.

If you have a timber door, once you have drilled the hole for the cylinder, go ahead and drill the small pilot holes required to fit your screws.

If you have a steel, aluminium or PVC door and the material or thickness of the frame won't allow you to insert your screws directly or use self-tapping screws, you will have to use rivet nuts, or blind nuts, to hold your screws. After checking everything is square using a spirit level, secure the lock in position. Fit the cylinder escutcheon on the outside of the door.

• Cylinder guards will either come with pre-drilled holes for fixing or may have threaded sleeves designed to hold screws. These sleeves are larger than the screws themselves. Start by drilling holes through the door just big enough for the screws to fit through.

• You can then remove your wooden block or plank, and the clamps. Measure the length and diameter of the cylinder guard sleeves.

• You can then make your holes bigger working from the outside of the door. Use a drill bit with a slightly larger diameter than that of the sleeves and make sure to drill to the correct depth.

• Place the lock on the door and connect the rim cylinder guard to the lock using the screws provided. Check that everything is square using a spirit level and secure the lock.

• Once your lock is in place, close the door and rotate the thumb turn or key to engage the bolt . Position the strike plate and mark out your screw holes using a pencil.

• If you have a timber door, remove the strike plate and drill a pilot hole in the door frame. The door frame may feature mouldings. In this case, you will have to trim down the moulding using a wood chisel before positioning the strike plate.

• Position the strike and secure it with screws. Use the longest screw possible to ensure a tight hold. If you have a steel, aluminium or PVC door and the material or thickness of the frame won't allow you to insert your screws directly or use self-tapping screws, you will have to use rivet nuts, or blind nuts, to hold your screws.

Screw length and type

Most locks come supplied with their own screws and the majority are designed for timber doors. However, you do need to check that they are the correct length for your frame – too long and they will protrude from the door face. If you have an aluminium door, you'll need specific screws (usually self-tapping screws or screws and rivet nuts). The length and type of screws required will be indicated in the instructions.

Required skills

You don't need any particular skills to fit a rim deadlock. As for most DIY jobs, you need to be able to take accurate measurements, be able to read instructions properly, know how to use a drill and pick the right drill bits, hole saw and screws for your surface.

Time required

Approx. 1 hour

Number of people required

1 person

Tools and equipment

• Slotted or pozidriv screwdriver (depending on your screws)

• Hole saw to drill the hole for the lock cylinder

• Wood or metal drill bits (depending on door material)

• Clamps

• Spirit level

• Tape measure

• Pencil

Please note that this is not an exhaustive list for all locks. Depending on your model, you might need a few extra tools.

Safety wear

• Safety goggles

• Protective gloves

Please note: this is a non-exhaustive list; be sure to match your personal protective equipment to the job at hand.