How Do I Install a Recessed Alarm Sensor in a Sliding Glass Door?

You can install a recessed alarm sensor in a sliding glass door by drilling holes into the door and its frame and then inserting the sensor and magnet into the holes. But this can be impossible if holes cannot be drilled into the door or its frame. Surface-mount sensors are best-used then.

The advantage to using recessed contacts is that the devices are invisible from the outside. This is because they are hidden inside of holes that are drilled into the door and its frame. However, if holes cannot be drilled, then recessed sensors cannot be used. Since many sliding glass doors are built from materials that make it difficult to drill holes, it is often better to just use surface-mount sensors instead.

If your sliding glass door is made of wood, then drilling the necessary holes shouldn't be much of a challenge. But vinyl and metal doors make the process considerably more difficult. For those doors, you might want to hire a professional or just use surface-mount door and window contacts. Alarm Grid has a previously written FAQ on installing door sensors on sliding glass doors that we encourage you to check out.

Both recessed and surface-mounted contacts operate in a similar manner. The difference is that recessed contacts are hidden out of plain sight inside the door and its frame. Surface-mount sensors are installed on the outside, and they remain visible. That being said, both types operate in the same manner, and they are actually very similar.

Door contacts function using a sensor and a magnet. Whenever the door is closed, the magnet should be in very close proximity to the sensor, possibly even in direct contact. Opening the door will cause the magnet to separate from the sensor. This will release a reed switch inside the sensor to activate it. The sensor will then alert the alarm control panel to let it know that the door has been opened.

Whether you use surface-mount or recessed contacts, you will want the sensor on or inside the door frame. Meanwhile, the magnet can go on or inside the door frame. The magnet is usually smaller than the sensor, so it can be easier to fit on or inside the door. Additionally, the sensor is more valuable than and prone to damage than the magnet. Keeping the sensor on the stationary part of the door and prevent damage.

Both wired recessed sensors and wireless recessed sensors are available. If you are using wired sensors, you will need to run wires directly to the panel. This can be difficult for many DIY installers. If you are using wireless sensors, you must make sure they communicate at a frequency compatible with your security system. Additionally, both types will need to be programmed to the system.

The steps below focus mostly on the actual installation of recessed sensors in a sliding glass door. Keep in mind that the steps will vary depending on whether the sensor is wired or wireless and the type of alarm system that is being used. Remember, this will only work if holes can be drilled into the sliding glass door and its frame. Complete the following steps to install recessed sensors in a sliding glass door:

1. Install the sensor. Open up your sliding glass door. Drill a hole into the door frame. The hole should be directly facing the sliding glass door. The hole should be the proper diameter and length to support the recessed sensor. Please see the manual for your recessed sensor to find out the appropriate dimensions. Then insert the sensor into the hole. The fit should be nice and snug.

2. Install the magnet. Drill a hole into the sliding glass door. Make sure that it is completely parallel and aligned with the hole you drilled into the door frame in Step 1. The hole should be the proper diameter and length to support the magnet. In most cases, the magnet is considerably shorter than the sensor, but it is usually the same diameter. You should review the sensor's manual for the dimensions. Then insert the magnet into the hole. The fit should be snug.

3. Complete the installation. The rest of the steps will depend on whether the sensor is hardwired or wireless. If the sensor is hardwired, run a connection wire from the sensor to the alarm panel or the appropriate transmitter. If the sensor is wireless, you can most likely auto-enroll it with the system. You may need to bring the panel close to the sensor when doing this. Go through and complete any necessary programming steps on the system.

4. Test the sensor. After installing and programming the sensor, you can begin testing the sensor. Close the door and check the system. The sensor should not be faulted, and the zone should not be displayed. Then open the door. The system should display the faulted zone. You might also want to test the sensor in various Arming settings to make sure the system responds how you want. Always place your system in text mode before doing this.