How to Measure a Patio Door

If you have an old sliding patio door, it could be time to replace it. Replacing sliding glass doors is a great way to update the look of your home and improve energy efficiency. Our experts at Apex Window Werks know that getting accurate measurements is key to finding the perfect new sliding glass door. Whether you’re looking to replace French doors, hinged patio doors, or sliding patio doors, you’ll need to take careful measurements of the existing frame. Follow this guide from Apex Window Werks for step-by-step instructions on measuring for sliding glass door replacement.

Necessary Tools and Equipment for Measuring

Measuring a patio door properly requires having the right tools on hand.

Here are the essential items you’ll need:

• Tape measure: Get an accurate tape measure that extends to at least 25 feet. This allows you to measure large openings without having to piece multiple measurements together;
• Pencil and paper: Have these ready to mark down the measurements as you take them. Use a pencil in case you to erase and redo any inaccurate marks;
• Level: A basic level helps you determine if the floor or door frame is perfectly straight or diagonal. This is key for accurate measurements;
• Screwdriver: You may need a screwdriver to remove any molding or hardware to measure the actual door frame underneath;
• Step ladder: If the door opening is high up, use a sturdy step ladder to reach the top points you need to measure.

These basic tools will make the measuring process much easier and more accurate when sizing replacement patio doors. Taking accurate measurements is crucial for ordering the correct new door.

Measuring Sliding Glass Doors

Sliding glass doors, sometimes called sliding patio doors, have some unique points to measure compared to hinged doors.

Here are the key measurements to take:

• Opening width: Measure the full width of the door opening at both the top and bottom. Use the narrowest width;
• Opening height: Measure from the bottom of the door sill up to the header;
• Existing door size: Measure the current door panels to determine the specific size you need to replace them. Measure the frame too;
• Condition of door track: Check if the bottom door track is level and not slanted. Also, note any damage;
• Condition of door frame and sill: Look for any rot or damage on the existing frame and sill which may need repair work when installing the new sliding door.

Be sure to measure the opening from multiple points at the top, middle, and bottom to account for any inconsistencies. Having a precise opening size ensures your new sliding patio door fits perfectly.

Measuring Hinged Patio Doors

Hinged patio doors, also called French doors, have a specific measuring process to follow.

We’ve outlined the steps:

• Measure opening width: Measure across the door frame from the inside edge to the inside edge at both the top, middle, and bottom. Use the smallest width;
• Measure opening height: Measure from the bottom of the door sill up to the header across the center of the opening on both sides. Use the shortest height;
• Measure door overlap: Note the amount of overlap the door has in the interior space when opened fully;
• Measure existing door size: Note the size of each existing door panel. Measure from the top edge to the bottom edge at the panels’ narrowest points;
• Measure frame details: Note the width and depth of the door jamb where it meets the wall. Check for any unusual frame details;
• Check for plumb: Use a level to determine that the sides of the opening are perfectly vertical;
• Note the thickness of the door jamb where it meets the wall;
• Check the floor for level and plumb the sides for square;
• Measure the frame recess: the inset distance from the door surface to the outer wall surface;
• Measure any molding or trim width around the door;
• Note which way the door swings and the presence of any doorsteps.

Don’t rush the measuring process! Accurately measuring for hinged patio and French doors ensures your new doors will fit the opening properly. If needed, have an assistant such as a friend or family member help hold the tape measure steady across large openings. Use a pencil to mark measurements before recording them.

Additional Maintenance to Consider During Measurement

In addition to taking measurements, we also recommend inspecting the overall condition of your existing patio door.

Look for:

• Signs of rot, water damage, or termites around the frame;
• Sliding door rollers that stick or grind;
• Hardware that’s loose, worn out, or missing;
• Glass that is cracked, broken, or foggy;
• Sealant and weatherstripping that’s damaged or missing;
• Door screen mesh that is ripped or frame that is bent;
• Misalignment that prevents proper closing and locking;
• Security issues like broken locks or damaged strikes.

Note any maintenance issues or repairs needed on your existing door during the measuring process. This will help you budget appropriately for the patio door replacement project. Always handle rotted wood, sealing issues, and security concerns promptly before you install a new door.

Reasons to Call a Professional Installer

While do-it-yourselfers can handle basic patio door measurements, in most cases, it’s best to call a professional installer for the actual door installation and some situations:

• If the existing frame is severely damaged or rotted, a professional can inspect and make all needed repairs;
• For unusual opening sizes, a pro can order a custom door made to your exact measurements;
• Professionals have specialized tools to properly shim, anchor, and seal the new door for optimum performance;
• If your home is multi-story, only experienced installers should handle upper-level patio door replacements;
• A general contractor may be needed for complex projects with both interior and exterior finish work.

While measuring can be DIY, professionals have the expertise to address tricky installations and ensure your new patio door operates smoothly for years. Make sure that the contractor is licensed, bonded, and insured before you hire them.

Get Expert Sliding Door Replacement with Apex Window Werks

For the best results, consider having Apex Window Werks‘ experienced professionals handle any necessary adjustments or repairs and install your replacement patio door. We proudly serve Illinois, Wisconsin, and Minnesota. Contact us today to schedule a free estimate to see how we can help!