How to Use a Tape Measure for Storm Door Installation & Home Projects

Whether you're taking measurements for a storm door or custom motorized screens, every project should start with accurate measurements. Learn the basics of how to use a tape measure to make fewer mistakes in your DIY projects and ensure the perfect fit for your door.
What Do the Lines on a Tape Measure Mean?
To better understand tape measure increments, extend your tape measure by pulling on the hook. You'll notice that the tape features lines of varying lengths at different increments of measurement. The longest tape measure increments represent whole inches.
Between every inch mark, you will see shorter lines. The shorter the line, the smaller the fractional inch reading is. From longest to shortest, these smaller lines represent 1/2 inches, 1/4 inches, 1/8 inches and 1/16 of an inch. Understanding these increments is crucial for accurate measurements and proper tape measure use.
How to Take Accurate Door Measurements
To take a screen or storm door measurement, extend your tape measure across the width of your doorway. Make sure the tape is inside the edges of the brickmold. Once you extend the tape measure to the full width of the door, take note of the inch mark and the next closest increment. For example, if your measurement passes the 31-inch mark but doesn’t reach 32 inches, and the end of your measurement falls on the seventh 1/8-inch mark, your final measurement is 31 and 7/8 inches.
When you measure the width of your doorway, take measurements across the top, middle and bottom of the frame and use the narrowest measurement as the width of your door. Then, measure the height of the threshold from the top to the bottom of the frame.
Tips for Using a Tape Measure When Installing a Storm Door
Tape measures include several helpful features to improve your measuring accuracy:
- Loose Metal Hook: Don't worry if the metal hook at the end of the tape is loose — it's designed that way. The hook goes in if you push the tape measure against something and comes out when it’s hooked to a nail or an edge. The hook itself is 1/16 of an inch thick, so the movement accounts for the thickness of the hook to ensure measuring accuracy.
- Hook Hole: The hole in the hook is designed to hook onto screws and nails to make it easier to measure without slipping or moving the measuring tape.
- Thumb Lock: The thumb lock keeps the tape from retracting automatically when you need to set it down or take multiple measurements. Just be careful when releasing the lock since the tape may snap back fast.
Get Started with the Larson DIY measurement guide
With these tips, you now have the knowledge to tackle your door project with confidence. Watch our how-to video to learn important home project measuring tips.