How To Measure French Doors

French doors add style, natural light, and a seamless connection between spaces. They can be used inside the home to divide rooms while keeping an open feel or as external doors leading to a patio or garden. Getting the measurements right is essential to ensure a perfect fit. A miscalculation can lead to gaps, drafts, and operational issues, making the doors less effective and harder to install.

Replacing existing doors, fitting new ones into a fresh opening, or upgrading to energy-efficient double glazing all require precise measurements. The right approach helps avoid costly mistakes and ensures smooth installation. This guide will walk through the steps for measuring internal and external French doors, covering essential techniques, common pitfalls, and expert tips. 

By following a structured process, it’s easier to find the ideal French door sizes and achieve a professional finish without unnecessary hassle.

Understanding French Door Sizes

Before taking measurements, it helps to understand standard French door sizes. French doors typically consist of two panels that open outwards or inwards, creating a wide and inviting doorway. The standard size for French doors varies, but most commonly, each door panel measures between 30 to 36 inches (76 to 91 cm) in width and around 80 inches (203 cm) in height. 

This results in a total width of approximately 60 to 72 inches (152 to 183 cm) for the complete set. However, external French door sizes may be larger to accommodate patio entrances, while internal doors are often smaller. For unique spaces, custom French door sizes can be ordered to fit non-standard openings.

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Tools You’ll Need to Measure French Doors

Before you begin, gather the following tools:

• Tape measure – Ensures accurate measurements.
• Notepad and pen – Keeps track of measurements.
• Level – Checks if the door frame is even.
• Pry bar – Helps remove old frame elements if necessary.
• Power drill – Assists with installation when replacing doors.

Measuring for External French Doors

External French doors serve as an elegant connection between indoor and outdoor spaces, such as patios or gardens. To ensure a proper fit, follow these steps:

1. Measure the Width

• Use a tape measure to check the width of the intended opening at three points: top, middle, and bottom.
• Write down the smallest measurement to avoid fitting issues.
• If replacing existing doors, measure from the inside edge of the old frame to the opposite inside edge.

2. Measure the Height

• Measure from the floor (or threshold) to the underside of the door frame at three points: left, center, and right.
• Again, record the smallest measurement for accuracy.
• If you’re installing external French doors that open onto uneven flooring, take the slope into account.

3. Check the Depth

• Measure the depth of the door frame to ensure the new doors fit properly within the space.
• For energy-efficient double-glazing options, check that there is enough room for the extra thickness.

Measuring for Internal French Doors

Internal French doors are a popular choice for dividing living areas while keeping an open, airy feel. Measuring for internal doors follows a similar process:

1. Measure the Door Opening

• Ensure the opening is square by measuring diagonally from corner to corner. If the measurements differ, adjustments may be needed.
• Take three measurements for width and height as done for external doors.
• If replacing existing doors, measure the doors themselves as well as the opening.

2. Consider Floor Clearance

• Ensure there is enough clearance for the doors to open smoothly, especially if installing over thick carpets or flooring transitions.
• Internal doors may require additional trimming for a perfect fit.

3. Check for Obstructions

• Identify any light switches, radiators, or furniture that could interfere with the door opening.

Additional Tips

• Check for Obstructions: Ensure that light switches, vents, or other fixtures won’t interfere with the door’s operation.
• Account for Trim and Molding: If you plan to add decorative trim or molding, factor this into your measurements.
• Professional Consultation: If you’re uncertain about any measurements or the installation process, consult with a professional to ensure accuracy and safety.

Ensuring Precise Measurements: Tips and Tricks

When it comes to DIY projects, precision is key. To help you on your quest for perfection, here are some insider tips and tricks that will ensure your measurements are spot-on every time

Double-Check All Measurements

We’ve all heard the old adage “measure twice, cut once,” and it couldn’t be more true. Even the best of us can make mistakes, so it’s crucial to double-check all measurements before proceeding with your project. Trust me; a few extra seconds spent verifying your numbers can save you hours of frustration later

Consistency is key when it comes to measuring accurately. By taking multiple measurements and comparing them against each other, you can catch any discrepancies or errors that might have crept in. Remember, precision always pays off!

Maintaining a Level Surface

If there’s one thing that can throw off your measurements faster than a greased-up banana peel on an ice rink, it’s an uneven surface. Before you start measuring anything, ensure that your workspace is as level as possible.

A trusty carpenter’s level will become your best friend in this quest for equilibrium. Place it on surfaces that need to be leveled (like countertops or floors) and adjust accordingly until the bubble rests right in the centre. With a reliable foundation underfoot, those precise measurements won’t stand a chance of going awry.

Common Mistakes to Avoid

1. Ignoring the Opening Circle

• French patio doors and double doors require extra space to swing open fully. Consider this when planning the installation.

2. Failing to Measure at Multiple Points

• The most accurate reading comes from measuring at multiple points and using the smallest dimension.
• Exterior doors are often slightly uneven due to house settling, making multiple measurements essential.

3. Overlooking Extreme Weather Conditions

• If installing external French doors, consider the impact of extreme weather conditions on materials. Wooden French doors may expand or contract, while uPVC and aluminium offer more resistance to temperature changes.

Related Reading: uPVC French Doors Not Closing Properly? Here’s How To Fix It

Choosing the Right Material for French Doors

When selecting new doors, consider the durable material best suited for your space:

• Wooden French doors – Classic and stylish but require maintenance.
• uPVC external French doors – Low maintenance and energy-efficient.
• Aluminium French doors – Strong, lightweight, and resistant to extreme weather conditions.

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Final Checks Before Installation

Once you have all the measurements, check the final width and height again before placing your order. Double-check the maximum width of the opening to ensure the doors fit comfortably without forcing them into place. If you’re installing double glazing, factor in the added thickness to ensure the frame accommodates it properly.

For most homeowners, ensuring accurate measurements at this stage will save time and prevent installation issues later. If in doubt, consider consulting a professional to verify your measurements before making a purchase.

Looking For Stylish French Door Options?

Taking the time to measure French doors correctly ensures a smooth installation and a perfect fit. By using a tape measure, checking at multiple points, and considering the door opening, you’ll avoid costly mistakes.

DoorsDirect2U have over 40 years of experience providing exterior and interior door solutions to suit all budgets and specifications. You can purchase with confidence safe in the knowledge all products are backed with a manufacturers guarantee.

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