Table of Contents
The short answer
You cannot know how many keys to your new front door exist. Previous tenants, their families and staff, agents, and the contractors who worked on the home may each have held one, and an ordinary key is copied in minutes. So change who can open the door in the week you move in. In most homes that does not mean a new lock. It means a new cylinder: the part the key goes into. The old keys stop working, you get new ones, and the handle and the lock inside the door stay as they are.
Change the whole lock when the lock itself is the problem: the bolt sticks, the handle droops, the case is worn or has been forced, the door has only a latch and no deadbolt, or you want a different kind of lock, such as a smart lock. If you rent, read your tenancy contract and ask the landlord or the building before anything on the door is changed, agree who holds a spare, and expect to hand every key back when you leave.
IHR Dream Cleaning's locksmith service lists key cylinder changes, door lock replacement and smart lock installation. There is no published price. The work is quoted by the lock type and the task, from photos or after a free inspection, before anything starts.
How a front-door lock is put together
The question in the title only makes sense once you know that a lock is two things. Many front doors in apartments and villas carry a mortice lock with a euro-profile cylinder. It has four parts.
- The handles, one on each face of the door.
- The lock case: a steel box set into a slot in the edge of the door, which is the mortice. It holds the latch, which the handle works, and the deadbolt, which the key works. All you see of it is the metal strip on the door's edge.
- The cylinder: a barrel with the keyhole in it, which passes through the case from one face of the door to the other. One screw through the door's edge holds it in.
- The keep, or strike plate: the metal plate in the frame that receives the latch and the bolt.
The cylinder holds the secret, the case does the work
Inside the cylinder, a row of small sprung pins has to be lifted to exactly the right heights by the cuts of the key before the barrel will turn. When it turns, a small cam on the cylinder pushes the bolt out of the case or draws it back. Because the two are separate parts, the secret can be changed without touching the mechanism. That is a cylinder change.
Cylinders come with a keyhole on both sides, or with a keyhole outside and a thumb-turn inside, which lets anyone leave without hunting for a key. They also come in many lengths, measured each way from the fixing screw, because doors and handle plates differ in thickness. The right one finishes nearly flush with the handle plate. One that stands out by more than a few millimetres can be gripped and attacked.
Other locks you may find
Not every door has a euro cylinder, and the answer to the title changes with the lock.
| Lock | How to recognise it | To change the keys |
|---|---|---|
| Mortice lock, euro cylinder | Keyhole-shaped barrel below a lever handle | Change the cylinder |
| Separate deadbolt | A second keyhole above the handle, with a turn inside | Change its cylinder, or the deadbolt |
| Knob or lever set | The keyhole is in the handle itself | Usually replaced whole |
| Lever mortice lock | A plain keyhole and a long key with a flat bit | The lock is replaced |
| Multi-point lock | Lift the handle to lock; bolts along the door edge | Change the cylinder |
| Smart lock | Keypad, fingerprint reader or card | Reset it, and change its backup cylinder |
When a new cylinder is enough
A cylinder change is the right job when the lock works and only the keys are in doubt. Check four things with the door open.
- The key goes in and comes out without wiggling, and turns smoothly both ways.
- The bolt throws fully and draws back fully.
- The handle springs back level, and the latch snaps out when you let go.
- With the door closed, it locks without being lifted, pushed or pulled.
Why it is the first choice
If all four are true, a new cylinder gives you everything a new lock would in terms of who can get in. It is also the gentlest option for a rented home. Nothing is cut and nothing is drilled, and the original cylinder can be put back when you leave if the landlord wants it. Keep it, with its keys, in a labelled bag.
It is quick as well. As a guide from our service page, a cylinder change or lock replacement typically takes 20 to 40 minutes a lock.
Three things to settle before the visit
The size: a locksmith measures the old cylinder, and a photo of the door's edge with a ruler held against it helps the right one to be brought. The inside: a second keyhole or a thumb-turn. And the keys: ask how many come with the cylinder, and have any extras cut at the same time. If several doors are being done, ask whether the cylinders can be supplied to work from one key.
Then count the doors. The front door is the obvious one. A villa may also have a kitchen or service door, a door from the garage, a side gate and a store. Every lock that a previous occupant held a key to is one to consider, and the number of locks changed in a visit is one of the things the quote depends on.
When the whole lock should go
A new cylinder in a tired lock gives you new keys to an old problem. Replace the lock case, or the whole set, in these cases.
- The mechanism is worn. The key turns but the bolt sticks or stops short, the handle droops, or the latch is slow to spring out. Those faults are in the case, and they end in a lockout.
- The door has been forced before. Split timber around the lock, a bent keep or a case that sits loose in its slot all mean the lock and its fixings need renewing, and the frame may need a carpenter first.
- There is no deadbolt. A door held only by a sprung latch is closed, not locked.
- It is a type that cannot be re-keyed by swapping a cylinder: a lever lock, or a knob set with the keyhole in the handle.
- It is rusted or seized. Locks on outside gates and garden doors take sun, dust and humid, salty air, and they age faster than the ones indoors.
- You want a different kind of lock: a thumb-turn inside, a tougher grade or a smart lock.
| Question | Cylinder only | Whole lock |
|---|---|---|
| What changes | The keyed barrel and the keys | Case, cylinder and often the handles |
| Do the old keys still work? | No | No |
| Cures a stiff or worn mechanism? | No | Yes |
| Work on the door | None | None if the sizes match; cutting if not |
| Can it be reversed at move-out? | Yes: refit the original | Only by refitting the old lock |
| Right when | The lock works and only the keys are in doubt | The lock is worn, damaged or the wrong type |
Will a new lock fit the old holes?
It should, if it is chosen by measurement and not by eye. The slot and the holes already cut in your door fix three dimensions: the backset, which is the distance from the door's edge to the centre of the keyhole; the centres, which is the distance between the handle and the keyhole; and the size of the case and its face strip. A lock that matches all three drops into the existing preparation. One that does not means cutting the door, filling old holes and sometimes new handles to cover the marks.
On our service, new locks are fitted to the existing door preparation where it is compatible, which is why the photos before the visit matter. The frame matters as much as the lock. For a replacement the door frame has to be in sound condition, because a strong bolt in a split frame holds nothing. A frame that needs repair first is work for carpentry.
Key control: who can open your door today
Locksmiths use the phrase key control for a simple idea: knowing how many keys exist and who holds each one. On the day you move in, you have none. Think about who may have held a key to this door before you.
- Previous tenants or owners, and everyone they gave a copy to: family, a housekeeper, a driver, a friend who watered the plants.
- The landlord, the agent and anyone who showed the home to viewers.
- Maintenance, painting and cleaning crews who worked in it while it was empty.
- In a new building, the developer's contractors and the inspection teams who had access before handover.
Resetting the count, and keeping it
None of these people need be dishonest for this to matter. Keys are lost, left in old handbags and passed on with a car, and a standard key carries no record of how many times it has been copied. Changing the cylinder sets the count back to the keys in your hand.
From then on, keep the count yourself. Give keys to people, not to hiding places, and do not tag a key with the address. If a key goes missing and could be linked to the home, change the cylinder again. Some cylinders are sold with a restricted key that can only be copied on showing a card that comes with the lock. If control of copies matters to you, in a home with staff or a flat that is let, ask about one.
Cards, fobs and remotes
A door key is only one of the things that open a home. Ask the building's management how many access cards, fobs and parking remotes are registered to your flat or villa, and have any that were not handed to you cancelled. Garage remotes and gate codes in a villa deserve the same question. The rest of the move-in walk-round, from the water tank to the sockets, is in the new home maintenance checklist.
If the home already has a smart lock
Changing who can open a smart lock means clearing its memory. Do a full factory reset by the maker's instructions, set a new master code, and register only your own codes, fingerprints and phones. Ask the previous occupant or the landlord to remove the lock from their app account, because on some models the first account remains the owner. Then remember the keyhole. A smart lock with a backup key still has a cylinder, and the old backup keys fit it until that cylinder is changed.
Security features worth asking about, in plain terms
Cylinders range from very basic to very resistant, and the packaging is full of terms. These are the ones that mean something.
| Term | What it means | When it matters |
|---|---|---|
| Anti-pick | Pins shaped so the lock resists being opened by manipulation | Any front door |
| Anti-drill | Hardened inserts that blunt a drill bit | Villas and ground-floor doors |
| Anti-snap | Breaking off the outer end of the cylinder does not open the lock | Wherever a cylinder stands out from the door |
| Restricted key | Copies are cut only on showing the card supplied with the lock | Homes with staff; let or shared homes |
| Works with a key in both sides | An outside key still works if one is left in the inside | Families, and anyone caring for an older relative |
| Thumb-turn inside | No key is needed to leave | A quick exit; less suitable beside breakable glass |
What matters more than the label
Three plain things do more for a door than any feature. The cylinder must be the right length, so that nothing stands out to be gripped. The door must close properly and the bolt must go fully home, because a deadbolt that only half enters the frame is half a lock. And the frame, the hinges and the keep must be sound.
After that, match the cylinder to the home. In a tower with a staffed security desk, the more realistic risk is somebody with an old key, and a correctly fitted cylinder with new keys deals with it. A villa with doors on several sides has more to gain from tougher cylinders, and its patio and kitchen doors deserve the same attention as the front. Ask whether a cylinder has been tested to a recognised standard and what grade it reached, tell the locksmith what you want the lock to resist, and ask what he would fit to his own door.
Smart locks: what to check before you buy one
A smart lock replaces the key with a code, a fingerprint, a card or a phone. It ends the question of how many keys exist, because codes can be added and deleted in a minute. That suits a home with staff, guests or children who lose keys. It also adds things a key never had: batteries, electronics and an account. Check these before buying.
- Door thickness and the existing lock. Every model lists the door thicknesses it fits and the size of case it needs. One that suits the existing cut-out goes on with little or no carpentry. One that does not means cutting the door.
- Door material and handing. Timber, metal and glass doors take different locks, and many models are made for a door hinged on a particular side or opening a particular way.
- Where the door is. An outside gate in sun, dust and rain needs a model made for outdoor use. Heat is hard on batteries and electronics.
- Batteries. Ask what type it takes, how it warns you when they are low, and whether it can be powered from outside if they die.
- The backup key. Most models have one. Decide where it will live, away from the home, before the lock goes on.
- The retrofit kind. Some smart locks fit over the inside of the existing lock and turn it for you. They leave the old cylinder in place, so the old keys still work until the cylinder is changed as well.
- Auto-lock. A door that locks itself behind you is secure, and it is also the easiest way to be shut out. What to do then is in locked out of your home.
- The account. The lock should be registered to you, and you should know how to transfer or delete it when you leave.
Fitting, and permission
Smart lock installation is on our service list, on compatible doors. Most standard doors are, but mention your door and the lock's brand and model when you book, so that compatibility can be checked beforehand. As a guide from our service page, installation usually takes 45 to 90 minutes including set-up and testing of the app or keypad, and the locksmith confirms that it works before finishing. Have your phone with you if the lock pairs with an app.
A smart lock changes the door more than a cylinder does, so the question of permission is sharper. In a rented home, get the landlord's agreement in writing, including what happens to the lock and the door when you leave. In a tower, ask the management office as well. The front door of an apartment is often a fire-rated door, and the building may limit what can be cut into it or fitted to its outer face.
If you rent: ask first, and hand the keys back
This guide does not say what tenancy law requires, and we do not give legal advice. What follows is the practical side, and it is the same whether you want a cylinder, a lock or a smart lock.
- Read the tenancy contract for anything about locks, keys or alterations.
- Ask the landlord or the agent in writing before changing anything. Say what you want to do and why. A cylinder change is a reasonable request, since it protects the property as well as you.
- Agree three things in the same message: whether the landlord wants a key to the new cylinder, who bears the cost, and whether the original goes back when you leave.
- Ask the building's management whether it has rules of its own. Some buildings keep front doors on a master-key system or want to approve what is fitted.
- Keep the original cylinder and its keys, labelled, where you will find them at the end of the tenancy.
- When you leave, hand back every key, card and remote you were given or had made, and either refit the original cylinder or hand over all the keys to the new one, as agreed.
At handover, and if you own the home
Keys are one item among many when a tenancy ends. What else an agent looks at is covered in the guide to move-out cleaning and your deposit.
If you have bought the home, the door is yours to change, but a tower or a managed community may still have a say in how the outside of a front door looks and in anything that affects a fire door. One email to the management office settles it.
When to do it in the move
Change the cylinder after the last person who needs a borrowed key has finished. An empty home sees painters, AC technicians and a cleaning team before the furniture arrives, and each of them needs a key or someone to open the door. If the cylinder is changed first, your new keys go out on loan in the first week, which is the thing you were trying to end.
So the order is repairs and painting, then the move-in clean, then the lock, then the furniture. If you cannot be there for the clean, lend one key and collect it the same day, or leave it at the concierge desk, and change the cylinder once it is back in your hand. If you are already living in the home, do it this week. Nothing about the job needs the home to be empty.
Booking the work, and what happens on the day
The quote depends on the type of job, the lock type and brand, whether the existing door preparation suits the new lock, and how many locks are done in the visit. Send these when you book.
- A photo of each door from outside, from inside, and of its edge with the lock's face strip in view.
- Any brand name or numbers stamped on the lock or the cylinder.
- The door's thickness, and whether it is timber, metal or glass.
- What you want: a cylinder, a whole lock or a smart lock, and a keyhole or a thumb-turn inside.
- How many keys you need. Key duplication depends on the key type, so mention extra copies when booking.
- Whether the home is rented, and that the landlord has agreed.
On the day
The locksmith needs both sides of the door and a clear space around it. A careful fitter tries a new cylinder or lock with the door open first, because a fault found with the door shut is a lockout. Then it is tested closed. The technician tests the lock and every new key with you from both sides of the door before leaving. Count the keys you are handed, and take the old cylinder if you are keeping it. If the lock needs a small adjustment after a few days of use, tell us and we will arrange it.
Payment is by card, online. Once the price is confirmed you pay online from My bookings on this website, and quoted jobs of AED 1,000 or more take a 30% advance by that link. Every price includes VAT.
Common questions
The home is brand new. Do I still need to change anything?
Often yes, for a different reason. Nobody has lived there, but contractors, inspectors and sales staff came and went for months. Ask the developer whether the keys you were given are the only set and how access to the unit was handled during construction. If the answer is vague, change the cylinder.
Can the existing cylinder be re-keyed and kept?
On some lock designs a locksmith can change the pins inside, so that a new key fits and the old one does not. With a euro cylinder it is usually simpler to swap the whole cylinder, which is a self-contained part. Ask which applies to your lock.
Can I change a cylinder myself?
Many people do. Two mistakes cause most of the trouble: buying the wrong length, and trying the new cylinder for the first time with the door shut. If you rent, remember that the hardware is the landlord's, and a part damaged or lost in the attempt is yours to answer for. If the old cylinder will not come out easily, stop and call a locksmith, because forcing it damages the case.
How many keys should I have?
One for each adult who lives there, and one spare kept away from the home with someone you trust. Write down who has which. Every key beyond that is one more to lose.
Do the bedroom and bathroom locks need changing?
No. They are privacy locks, not security locks. Check that each one works, and that the bathroom locks can be released from outside in an emergency, which matters with small children in the home.
I lost a key six months later. Do I start again?
Only the cylinder. If the key could be connected to your address, because it was lost with a bag, a parcel label or a car, change the cylinder and have new keys issued. If it fell down a drain on holiday, it is your decision. The lock case, the handles and the door stay as they are either way.
Where to start
Open the door and run the four checks. If the lock passes, ask for a cylinder change. If it fails, or you want a smart lock, send the photos and say so. If you rent, write to the landlord today, since that reply is usually what takes longest.
The scope of the work is on the locksmith service page, and you can book online or in the IHR Dream app. We work every day, 8 AM – 8 PM.
