A gap beneath the door may involve the seal, the way the door sits or the floor itself. Describe whether the gap is even across the width or concentrated at one corner. A larger seal is not automatically the right repair.
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Look at the shape of the gap
From a safe position, note where light or debris passes through. Mention whether the gap appeared suddenly or has always been present. If the door now sits crooked or has loose lifting hardware, stop using it and treat the issue as more than weather sealing.
Ask what each proposed fix addresses
A compatible seal can address a suitable sealing problem. A floor condition or a door-position problem may require different work. Ask the provider to distinguish these possibilities and explain any limitation. Do not increase closing force simply to press the door harder against the floor.
Frequently Asked Questions
Will a bottom seal prevent every kind of water entry?
No. Drainage and driving rain can involve conditions beyond the seal. Describe the actual water pattern for assessment.
Can I adjust the opener until the gap disappears?
Do not use force or travel changes to mask an unresolved door or floor issue. Have the cause identified first.