Size Measurement Guide: What Every Homeowner Should Know

2022-09-28 6 min read Garage Door Middleboro Team

Whether you're replacing an existing garage door, building a new garage, or simply curious about sizes, understanding garage door dimensions is essential. Accurate measurements ensure proper fit, optimal operation, and can save you time and money on your project.

Standard Garage Door Sizes

Before diving into measurement techniques, let's review standard garage door sizes. Knowing these can help you understand your options and compare with your current or planned door.

Single-Car Garage Doors

The most common sizes for single-car garage doors are: - 8' x 7' (Width x Height) - Standard size for older homes - 9' x 7' - Modern standard, accommodates most vehicles - 10' x 7' - Wider option for larger vehicles or additional clearance - 9' x 8' - Taller option for trucks and SUVs

Double-Car Garage Doors

For two-car garages with a single door: - 16' x 7' - Standard double door size - 16' x 8' - Taller option for larger vehicles - 18' x 7' or 18' x 8' - Extra-wide options for added clearance

RV and Oversized Doors

For RVs, boats, or commercial applications: - Heights can extend to 12' or more, Widths may reach 20' or beyond, Custom sizes are often necessary

How to Measure Your Garage Door Opening

Accurate measurements are crucial for ordering a replacement door. Here's a step-by-step guide:

Step 1: Measure the Width

Measure the width of the door opening at the widest point. Take measurements at both the top and bottom of the opening, as walls aren't always perfectly straight. Use the smaller of the two measurements.

For a proper fit, doors are typically manufactured 1-2 inches smaller than the opening width to allow for the frame and weatherstripping.

Step 2: Measure the Height

Measure from the floor to the top of the opening. Take measurements on both sides and use the smaller value. As with width, doors are made slightly shorter than the opening height.

Step 3: Measure the Side Room

Side room is the space between the door opening and the side walls of the garage. You'll need: - Minimum 3.75" on each side for standard track installation - Additional space for low headroom or specialty track configurations

Measure from the edge of the door opening to the nearest obstruction (wall, cabinet, pipe, etc.) on each side.

Step 4: Measure the Headroom

Headroom is the space between the top of the door opening and the ceiling or nearest obstruction. Requirements vary based on the track system: - Standard lift: 12-15" minimum - Low headroom: 4.5-10" (requires special hardware) - High lift or vertical lift: Requires additional headroom

Measure from the top of the door opening to the ceiling or lowest obstruction.

Step 5: Measure the Backroom (Depth)

Backroom is the distance from the door opening to the back wall of the garage. This determines how far back the door will extend when open.

For standard extension spring systems, you'll need: - Door height plus 18" for standard tracks, Door height plus 6" for low headroom configurations

Step 6: Note Any Obstructions

Look for anything that might interfere with door or track installation: - Light fixtures, Pipes or ductwork, Electrical panels, Water heaters, Ceiling joists orientation

Document the location and dimensions of any obstructions so your installer can plan accordingly.

Special Considerations

Measuring for Replacement

When replacing an existing door, you have two options:

1. Measure the existing door: This gives you the exact door size currently installed 2. Measure the rough opening: This allows for potentially upgrading to a different size

For replacements where you're keeping the same size, measuring the existing door is simpler. Measure the actual door panels, not the frame or tracks.

Uneven Floors

Many garages have sloped floors for drainage. If your floor is uneven, note the highest and lowest points within the door opening. Your installer can adjust the bottom seal to accommodate the slope.

Non-Standard Openings

If your measurements don't match standard sizes, don't worry. Many manufacturers offer custom sizing. Costs are typically higher and lead times longer, but you can get a door that fits your specific opening.

Tips for Accurate Measurement

1. Use a steel tape measure - It won't stretch and provides consistent readings 2. Measure twice - Always double-check your measurements 3. Write everything down - Don't rely on memory 4. Take photos - Document the opening and any obstructions 5. Note existing hardware - Record track type, spring system, and opener model

When to Call a Professional

While taking basic measurements is straightforward, there are situations where professional measurement is advisable:

- Non-standard or unusual openings, Low headroom situations, Concerns about structural issues, Planning for opener installation simultaneously, Commercial or industrial applications

At Garage Door Middleboro, we offer free measurement and estimates for all garage door projects. Our experienced technicians will ensure accurate measurements and help you choose the perfect door for your needs. Contact us today to schedule your free consultation.

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