Check the Limit Switch Settings
Check The Door Weather Seal
Check The Seals Around The Garage Door
Rubber seals tend to be found on newer garage doors and when the door is closed, they prevent entry of draughts and dust. These can sometimes become tangled and prevent the door closing correctly, leading to a gap forming below the door.
Check the Tracks and Spindle Rollers
Any obstructions in the tracks could be causing the gap so please clean them of any debris. Also check the spindle rollers. Are the rollers significantly worn? If so, it could be causing the door to close at an angle leading to the gap.
Spindle rollers can be replaced, but if uncomfortable making these repairs, please contact a handyman or garage door repair company.
Fix the Concrete Slab
Over time the concrete slab in the garage can settle lower, resulting in a gap between the bottom of the door and the floor. Having a new concrete slab poured can be expensive, but a cheaper option is to have the concrete topped up to level the floor and remove the gap.
You should now be able to secure your door, remove the unsightly gap, and prevent the ingress of water, vermin, and leaves. We have covered the main reasons for there being a gap under the door, but sometimes the problem could be something else.
If these steps did not help, and you are unable to determine the cause of the problem, we recommend contacting a local garage door repair company and asking for assistance.