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3 Patio Door Lock Replacement Tips Experts Think You Should Know

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You have put off your patio door lock replacement long enough! It is time to get all the locks in your house working properly. Stop using chains, childproof locks, and other eyesore devices to secure your door. Sliding patio door lock replacement can seem especially daunting, but it is worth it so you can get the most out of your security.

Everything you need to know about patio door lock replacement breaks down to:

  1. Buying Parts
  2. Types of Locks
  3. Replacement Process

Patio Door Lock Replacement or Refurbishment?

It is almost always true that fixing a lock will be less expensive than a full replacement. For patio door locks, this is rarely the case. Often these locks will break in a way that necessitates full patio door lock replacement. It can also be more difficult to find replacement parts sold separately. You may end up having to buy an entirely new lock assembly even if only one component of your lock is broken.

It is also beneficial to do a full patio door lock replacement in several instances. For example, changing locks on a new home should include all keyed entrances to a property. It is unlikely that you will be able to rekey the patio door lock because most of the keyed cylinders are not removable. So to change access you will need patio door lock replacement. 

Common issues include misaligned catches, broken latch springs, and sheared handles. When you determine your issue, see if you can get your hands on what you need to avoid full patio door lock replacement. Misaligned catches should require no purchasing at all. Simply lower or raise the catch so the latch properly slides inside.

If you want to avoid patio door lock replacement because you desire to keep existing locks for their style or historical value, this may be more difficult. Antique lock repair is best left in the hands of a locksmith, as they have the knowledge and ability to accurately diagnose the problem and find replacement parts.

Key Takeaways:

  • A broken patio door lock almost always needs to be replaced.
  • Rekeying patio door locks is rarely possible due to their design.
  • If replacement is not desired, you must find and replace the damaged component(s).
  • Misaligned latch and catches can be realigned by moving the catch up or down.

Buying Parts

Buying patio door lock replacement parts is step zero. You want to make sure that you have the correct replacement parts before starting even the first step of patio door lock replacement. Most often this will require at least a surface-level understanding of the lock you are using and available options for new parts. A residential locksmith can provide this information if you cannot find it yourself.

Considerations for new parts include:

  1. Size and Fit
  2. Security Upgrades
  3. Fixing Your Issue

1. Find Your Fit

If you do not intend to change your patio doors, it is imperative that you match your replacement locks perfectly. Patio door lock replacement starts with buying products with the proper size and fit. To get these measurements, you may need to remove the lock, especially if this is a mortise lock.

For mortise latch locks, which are common on most vinyl sliding patio doors, you want to pay attention to certain lengths and shapes. Mortise lock bodies are almost fully obscured when they are installed, so assessment requires disassembly.

Take note of rounded or square edges on the faceplate of the lock. Check if the keyway rests at a slanted 45-degree angle or stands vertically. The housing of these locks may vary between square and inclined/slanted. Also, note if the mounting holes extended out the same distance from one another.

Besides mortise patio door lock replacement, there are other types of door locks you may need to replace. These will be discussed further in the sections below, but follow the same assessment process as was outlined for mortise locks. Essentially, measure everything against the products you are looking to buy.

Key Takeaways:

  • Determine which type of patio door lock you are using.
  • Measure the dimensions of your current lock.
  • When changing the style of lock you are replacing, consider if the door will need to be changed to fit the new lock.

2. Security Upgrades

When you are replacing a patio door lock, you may consider the various ways a new type of lock can add security. Although most people want to do everything they can to prevent a burglary, patio door lock replacement is rarely going to provide this opportunity. This is especially true in the case of securing a sliding glass door.

In terms of getting a return on your security investment, patio door lock replacement is often inherently undermined by the door. The patio door likely uses glass, so a better lock is not going to offer as much as strengthening the glass with security film. I would recommend saving money on the lock, settling for something convenient to lock and invest in other aspects of security.

Key Takeaways:

  • Patio door lock replacement rarely has the potential to add security.
  • Convenience is most important with patio door lock replacement to ensure you use the lock reliably.
  • Sliding glass patio doors can be improved with security film.

3. Fix Your Issue

Not ever sliding patio door lock replacement will solve the problem you are experiencing. This is because not every problem has to do with the lock hardware. Say you are confronted with a latch or bolt that will no longer secure into its housing. You may be able to temporarily fix the issue with a patio door lock replacement, but it could recur.

Sliding patio door lock replacement is commonly misprescribed for foundation problems, wood expansion, and improperly installed sliding doors. If any of those three issues are the cause of the door lock problem, the only thing a patio door lock replacement is going to do is buy you a bit more time before you have to solve the larger problem. And it may not provide very much time before the door lock begins malfunctioning again.

Key Takeaways:

  • Patio door locks can malfunction even when the lock is working properly.
  • Fountain shift, door installation, and wood expansion may be the root of your patio door lock problem.
  • Patio door lock replacement may temporarily solve symptoms but the problem will recur.

Types of Patio Door Locks

Depending on the door locks, the replacement process will have certain variations. They still include the basic tenets of all lock installations, but each will have certain additional considerations. Before moving straight to the patio door lock replacement, look at the information about your specific type of lock.

The main types of patio door locks are:

  1. Latch Locks
  2. Handles
  3. Door Jamb Bolts

1. Latch Locks

Patio door locks often use a latch system either installed on or inside the door(s). Commonly, sliding patio door lock replacement on vinyl doors will deal with mortise-style latch locks. These locks slip inside a pocket within the door and have a latch housing installed on an apposing sliding door or the door jamb. Be sure to secure the mortise lock body during disassembly so it does not fall into the door as you remove the set screws.

The other type of latch lock your sliding patio door lock replacement may be dealing with resembles a rim lock, as the hardware and latch housing installs outside of the door. This style of patio door lock is relatively easy to install but you have to be sure that the housing and latch line up parallel to one another as well as at the correct height.

2. Handles

When it comes to patio door lock replacement, you may not have a problem with the lock itself, but instead, just need to replace the handles. Sometimes patio door handles can get sheared off or break off during use. They can also become weathered to the point where you can not fix the loose door handle.

Proper replacement will deal with the set screw distance and the fit over the locking mechanism. Patio door handle replacement will be more straightforward than changing a standard door knob because they are not mechanical devices.

Handles for patio doors are almost always fixed, meaning they do not turn or rotate in order to retract a latch or bolt. Just make sure that the handle is not installed over the lock until the tolerances are adjusted and the patio door can lock and unlock properly.

3. Door Jamb Bolts

Door jamb bolds are more common for french doors (double doors), but you may also see these devices with sliding patio doors. These locks are simple bolts that slide up into the top of the door jamb or down into the bottom of the door jam.

In their simplest form, the bolt has the construction of a billy club (tonfa). The long end secures into the door, and a short end sticking out perpendicularly, which is used to move the bolt. To install these, there only needs to be a hole or housing for the bolt to slip into.

If you are looking for purchasing options, there are variants of this lock which are referred to as “foot locks”. Foot locks work a bit differently from standard door jamb bolts because they use throw and release buttons, which are operated with your foot. This added convenience assures that it will never be too much of a hassle to use the lock.

Patio Door Lock Replacement 

Always refer to the installation instructions that come with your replacement patio door lock. The documentation your lock comes with takes precedence over any of the following information. If you have any questions, call a professional locksmith. With that being said, there are some good general processes to stick to. 

The steps of patio door lock replacement break down to:

  1. Opening the Door
  2. Disassembly
  3. Installation
  4. Testing

1. Opening The Door

When it comes to many of the different patio door locks, you will be able to remove them without having the door open. And in some instances, the lock itself will not need to be open. Locks can be opened once they are partially disassembled or opened by virtue of being removed. You will just need access to the interior of the home, which is only a problem if you are locked out of your house.

If you are using a mortise latch lock, you will have to get the door open in order to continue with the patio door lock replacement. Opening the door will be very similar to unlocking a bathroom door lock, as this latch is not designed for security. But if the lock is broken, call a locksmith so you do not run the risk of damaging the door.

You should not have to worry about unlocking the door without a key because you should have access to the interior of the home where a key is not used. In the event that you are locked out of the room, you will need a locksmith’s lockout service. It is not recommended that you try to force the door open, especially if it is a sliding glass patio door.

2. Disassembly

When it comes to patio door lock replacement, things can start to truly go wrong during the disassembly process. In the case of sliding patio door lock replacement, you want to be very careful not to have your tools hit the glass. Excessive pressure from power tools or slipping tools can damage or even break the glass.

Besides being gentle, there is also the concern of losing track of parts. Springs and latches that may have broken loose can fall into the door and create all kinds of headaches. Mortise locks installed inside vinyl sliding doors are at risk of falling through/inside the door, so steps must be taken to hold them in place as set screws are removed.

On the optimistic side of things, the disassembly aspect of patio door lock replacement gives you the opportunity to see how your lock works. During this step, you may find that the lock cylinder is removable and you will have the option of rekeying or replacing your lock. Though it is possible that rekeying will not solve the problem with your lock.

3. Installation

The lock installation aspect of patio door lock replacement can either be the most complicated or the least depending on what you are trying to achieve. The least complex version of installing a new patio door lock is achievable by replacing the broken lock with the exact same style and brand.

The most complex patio door lock replacement comes from using a new lock, which requires new holes or changes to the patio door. If you have opted for the simple patio door lock replacement, you can reverse the disassembly steps and the lock should install correctly.

When in doubt, just refer to the documentation that came with your new patio door lock. Be sure not to completely tighten one screw until every screw is partially inserted. One screw fully tightened before others can lead to issues with the lock fitting properly.

Complex patio door lock replacement is best left to a residential locksmith. If you have to make significant changes to your door, you need to do it correctly the first time, or you run the risk of needing a full patio door lock replacement. If you insist on doing this work yourself, the best advice I can give would be to measure twice and cut once.

4. Testing

Lock and unlock the door several times to make sure the issue you were experiencing before the patio door lock replacement has been fixed. You may find that the door lock sticks or only turns when excessive force is applied. This is very common, especially after sliding patio door lock replacement where an external latch lock is used.

The solution should be less complex than when a door knob is stuck, and only requires you to adjust the tolerances on the lock so everything is less tight. You may also find it necessary to shorten the tailpiece on the cylinder or add a spacer to give a bit more distance between the tailpiece and lock actuator.

Closing Thoughts

For more information or assistance with performing your patio door lock replacement, be sure to contact a professional locksmith. You do not want to damage your patio door or tracks, as that is guaranteed to create more than just security problems. A mobile locksmith service can provide you with everything you need to get this work done quickly and safely. Call United Locksmith today!

Category: Lock Types, Residential


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