A garage door that won't fully close represents a number of problems: not only is it a security risk, allowing potential thieves a way into your garage or home where they can gain access to your belongings, it can also reduce the insulative qualities of your garage, reducing comfort levels within your home, and allow animals and insects easier access to the interior of your house as well. There are a number of reasons why your garage door may no longer be able to close all the way: understanding what some of the most common causes are can help you troubleshoot the issue and get everything back to normal again as soon as possible.
Blocked or Misaligned Sensors
Most modern garage doors have a safety feature built in that is made up of two sensors that link an invisible beam of light between them. When the beam is broken by an object or a person, the opener will stop working to prevent the door coming down on something. Damage to the sensors, including dirt over the light or misalignment that prevents the sensors from seeing each other, is one of the most common reasons why your door may not move at all, or only come down part way. Cleaning the sensors and getting them back into alignment can get your door working again properly: if severely out of alignment, you may have to contact a professional to install it back in place.
Broken Door Springs
The springs in your garage door contain the tension necessary to lift and lower the garage door. These springs are under a massive amount of pressure, and as such any sort of damage can cause them to break or otherwise snap. If you observe any separation in the springs along the side of your garage door, you should get in touch with a professional to replace them: avoid working on them yourself, since the massive amount of pressure that they are under makes them particularly dangerous.
Finally, another one of the most common reasons why your garage door won't close properly is because the track of the door is somehow damaged. Sometimes, this is just because of dirt and debris which has become stuck in the track, which can be easily fixed by cleaning the track out by hand. Other times, the track has become physically misaligned due to damage or pressure, or has suffered from rust and corrosion, preventing your door from moving along the track properly. In either of these two cases, a professional will have to come in to either repair the track when damage is minor, or replace it entirely if it has failed structurally.
Contact a company like Mid-South Door Co for more information.