January 5, 2024 6 min read Leetonia Garage Doors Team
Whether you're replacing an existing door or planning a new installation, accurate measurements are essential for a proper fit and smooth operation.
- Step ladder, Pen and paper or smartphone for notes, Helper for large openings
Width Measurement 1. Measure the width of the door opening at the floor level 2. Measure again at the header (top of opening) 3. Use the narrower of the two measurements 4. Round down to the nearest inch
Standard widths: 8', 9', 10', 12', 14', 16', 18'
Height Measurement 1. Measure from the floor to the bottom of the header 2. Measure on both sides 3. Use the shorter measurement 4. Round down to the nearest inch
Standard heights: 7', 8'
Sideroom (Jamb Width) Measure the distance from the door opening to: - Side walls, Shelving or obstructions, Garage door opener rail
Minimum sideroom required: 3.75" - 5.5" depending on hardware type
Headroom Measure from the top of the door opening to the ceiling or lowest obstruction.
Minimum requirements: - Standard lift: 10" - 12" - Low headroom: 4.5" - 9.5" (special hardware required)
Backroom (Depth) Measure from the door opening to the back wall.
Requirements: - Door height plus 18" for standard installations, Additional space for opener if ceiling-mounted
1. Measuring the old door instead of the opening 2. Ignoring obstructions like pipes, lights, or garage door openers 3. Forgetting slope on uneven garage floors 4. Not accounting for weatherstripping thickness
Even small measurement errors can result in: - Doors that don't fit properly, Gaps that let in weather and pests, Safety hazards from improper installation, Voided warranties
At Leetonia Garage Doors, we provide free professional measurements with every quote. Our experts ensure your new door fits perfectly. Contact us for a new installation consultation today.