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A Complete Guide to Measuring Door Frames

Date Published: 29th March 2024

Category Doors & Windows

Author: Robyn

How to Measure a Door Frame Correctly

Accurately measuring door frames is vital to ensuring a seamless installation. From height to width, understanding the ins and outs of door frame measurement guarantees that the doors work as they should. It also prevents potentially expensive mistakes and saves you time, too.

Whether you're renovating or involved in a new construction project, measuring a door frame correctly is a fundamental skill you need to master. It ensures a snug fit and enhances the overall aesthetic appeal of any space.

Learn all about how to measure a door frame in our comprehensive guide.

Types of Door Frames

Door frames come in various materials, ranging from wood to metal, fibreglass, and uPVC. At Buildworld, you can find a variety of high-quality door frames, predominantly in hardwood and oak veneer, designed to fit most standard doors.

Measuring Tools for Door Frames

To accurately measure any type of door frame, you'll need:

Carpenter's Squares

Carpenter's Squares: This tool ensures that corners are 100% perpendicular for accurate measurements.

Combination Squares

Combination Squares: Useful for marking your door frame and checking that the right angles are correct.

Digital Callipers

Digital Callipers: A digital calliper allows you to make detailed changes, precise measurements, and fine adjustments.

Laser Measures

Laser Measures: Provide quick, accurate measurements and are perfect for bigger projects.


Levels: Ensure that door frames are plumb and straight.

Plum Bobs

Plum Bobs: Verify vertical alignment, which is especially important when dealing with tall doors and/or uneven floors.

Scribing Tools

Scribing Tools: Help transfer the irregularities of floors or walls onto the door frame to ensure a perfect fit.

Tape Measures

Tape Measures: The only way to accurately determine depth, height, and width is to use a tape measure.

Step-by-Step Door Frame Measuring Guide

  • Gather your tools.
  • Measure width. Take three measurements horizontally - top, middle, and bottom of the door frame. Record the smallest measurement.
  • Measure height. Take three measurements vertically - left, centre, and right sides of the frame. Record the tallest measurement.
  • Check for squareness. Use the carpenter's square to ensure the corners are at 90-degree angles.
  • Check for level. Place the level vertically and horizontally to ensure the frame is plumb and straight.
  • Note any irregularities. Observe any uneven surfaces or protrusions that may affect the installation.
  • Double-check measurements. Confirm all measurements before proceeding to ensure accuracy.
  • Record measurements. Note down all measurements carefully for reference during door selection and installation.

Measuring for Replacement Doors

Measuring Replacement Doors

When you're replacing an existing door, precision is key. Follow these tips for accurate measurements:

  • Measure the width and height of the current door frame at 3 points: the top, the middle, and the bottom.
  • Account for any irregularities in the door frame and/or surrounding walls.
  • Consider the direction of the door's swing and the placement of the handle to ensure the door is properly oriented.
  • Measure the door's thickness to make sure that the replacement is compatible with the existing frame.
  • Check the clearance around the door to ensure it operates smoothly.
  • Double-check each one of your measurements to prevent potentially costly mistakes.

Common Measuring Mistakes

Common door frame measuring mistakes include:

  • Inaccurate Measurements
  • Rushing or using improper tools can lead to incorrect dimensions.
  • Ignoring irregularities
  • Failing to account for uneven walls or floors results in ill-fitting doors.
  • Neglecting clearances
  • Overlooking space for hinges, handles, and door swings leads to functional issues.
  • Forgetting to check squareness
  • Uneven corners cause misalignment, hindering proper installation.
  • Misinterpreting dimensions
  • Misreading measurements or overlooking details results in incompatible doors.

Avoid these errors by using precise tools, measuring multiple times, accounting for irregularities, and consulting professionals if unsure. Double-check all measurements and consider all factors for a flawless door frame fit.

Measuring for Different Door Types

Different Door Types

Depending on the type of door you are installing, you may need to adjust the way you measure or add on measurements to ensure the door fits flush. If you are installing double doors or French doors, ensure that you measure correctly for each door, even if the frame is a single unit.

Adjusting Measurements for Fit

To ensure a perfect door installation, follow these steps to adjust door frame measurements accurately:

Add Clearance: Account for the door's thickness and the space needed for hinges and handles when measuring the width.

Consider Swing Direction: Adjust the measurements to accommodate the door's swing direction, ensuring it doesn't obstruct nearby objects.

Account for Flooring: If the flooring is thick, raise the door frame height accordingly to avoid scraping.

Shim for Squareness: Use shims during installation to correct any discrepancies in the frame's squareness.

Double-Check: Verify all adjustments before proceeding to ensure a snug fit and smooth operation.

Understanding Door Frame Terminology

Casing or Trim

Casing or TrimDecorative moulding around the perimeter of the door frame that conceals gaps between the frame and the wall.

Door Frame

Door FrameThe structural framework surrounding a door that typically consists of 2 vertical jambs and 1 horizontal head.


HeadThe horizontal top part of the door frame.


HingeA hardware component that allows the door to swing open and close, typically attached to the jamb and door edge.


JambThe vertical side of the door frame, against which the door closes.


RevealThe space between the door and the frame when the door is closed.


StopA thin strip of wood or metal that prevents the door from swinging too far inward or outward when closed.

Strike Plate

Strike PlateA metal plate affixed to the jamb where the latch or bolt of the door lock engages when closed.


ThresholdThe bottom part of the door frame, where the door rests when closed, often fitted with a strip to seal against drafts and moisture.


SillA horizontal component beneath the threshold, often used in exterior door frames to prevent water infiltration.

Measuring for Custom Doors

Follow these guidelines when you're measuring for customer doors:

  • Measure the width of the door frame at three points: top, middle, and bottom. Take the smallest measurement to ensure clearance.
  • Measure the height of the door frame at the left, centre, and right sides. Record the tallest measurement to accommodate any variations in floor or ceiling height.
  • Measure the depth of the door frame to ensure compatibility with the custom door's thickness.
  • Account for any irregularities, such as uneven walls or flooring, and adjust measurements accordingly.
  • Add space for hinges, handles, and door swings when determining width and height measurements.


At the end of the day, it's all about precise door frame measurements. When you've accurately measured the door frame's depth, height, and width, you're ensuring everything fits and works properly. Whether you are replacing an existing door or installing a custom one, measure precisely to avoid delays, expensive errors, and general frustration!


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