Complete Window Shade Measurement Guide

Accurate measurements are the foundation of a perfectly fitting custom printed window shade. This comprehensive guide walks you through every step of measuring your windows for both inside mount and outside mount installations. Taking your time with measurements ensures your shade fits beautifully and operates smoothly for years to come.

Before you begin, gather these tools: a steel measuring tape (25 feet recommended for large windows), pencil and paper for recording measurements, step stool or ladder for high windows, and optionally a helper to hold the tape for wide windows.

Understanding Mount Types

Inside Mount

Inside mount shades fit within the window frame opening, creating a clean, built-in appearance. This is the most popular mount type for residential windows. Inside mount requires adequate depth in your window frame—at least 1.5 inches for standard shades and 3 inches for motorized shades. The shade will be slightly narrower than the window opening to allow clearance for smooth operation.

Inside mount is ideal when you have beautiful window trim you want to showcase, when you want a minimalist built-in look, or when wall space around the window is limited. It provides the cleanest appearance but offers slightly less light blockage around the edges compared to outside mount.

Outside Mount

Outside mount shades mount on the wall or trim above and around the window frame. The shade covers the entire window opening plus additional overlap on all sides. This mount type is necessary when your window frame lacks sufficient depth for inside mount, and it is preferred when maximum light blockage is important.

Outside mount is ideal for shallow window frames, maximizing light blockage, making windows appear larger, covering multiple windows with a single shade, or when you prefer the shade to be a prominent design feature rather than recessed. The shade can extend as far beyond the window as you desire.

Inside Mount Measurement Steps

Follow these steps carefully for inside mount installation

Measure Width at Three Points

Measure the inside width of your window opening at the top, middle, and bottom. Record all three measurements. Windows are rarely perfectly square, so measuring at multiple points ensures accuracy.

Use the Smallest Width

Record the SMALLEST of your three width measurements. This is your ordering width. We will make slight deductions (typically 1/4 inch total) to ensure the shade clears the frame and operates smoothly.

Measure Height at Three Points

Measure the inside height of your window opening at the left, center, and right. Measure from the top of the frame where the brackets will mount to the window sill or bottom of the frame.

Use the Longest Height

Record the LONGEST of your three height measurements. This ensures the shade fully covers the window opening at all points.

Measure Frame Depth

Measure the depth of your window frame from the front edge to the window glass. You need at least 1.5 inches for standard shades, 2.5 inches for shades with valance, and 3 inches for motorized shades.

Outside Mount Measurement Steps

Follow these steps for outside mount installation

Determine Coverage Area

Decide how far beyond the window frame you want the shade to extend. For optimal light blockage, we recommend 2-3 inches of overlap on each side and at least 3 inches above the frame.

Measure Total Width

Measure the total width you want the shade to cover—this is your ordering width. For example: 36-inch window + 3 inches left overlap + 3 inches right overlap = 42-inch ordering width. No deductions are made for outside mount.

Measure Total Height

Measure from where you want to mount the brackets (typically 3+ inches above the window frame) to where you want the shade bottom to stop (typically 2+ inches below the window sill).

Verify Mounting Surface

Ensure you have solid material for mounting—wall studs, wood header, or sturdy trim. Avoid mounting into drywall alone. If mounting into drywall, use appropriate toggle bolts rated for the shade weight.

Special Measurement Situations

Measuring for Multiple Windows

When measuring multiple windows in the same room, measure each window individually even if they appear identical. Manufacturing variations and settling can cause seemingly matching windows to differ by 1/4 inch or more. Label each measurement clearly with the window location.

Windows with Handles, Cranks, or Locks

For inside mount on windows with protruding handles, cranks, or locks, measure the depth of these obstructions. The shade brackets and rolled fabric must clear these items. If clearance is insufficient, consider outside mount or using spacer brackets that project the shade away from the obstruction.

Bay Windows and Angled Installations

For bay windows, measure each window section separately. Note any angles between sections. For angled or skylight installations, specify the angle and whether the shade will operate with gravity assistance or against it—this affects hardware selection.

French Doors and Doors with Windows

For doors with windows, measure the glazed area rather than the full door. Consider whether the shade needs to clear door handles when raised. Outside mount extending onto the door frame is often the best approach for French doors.

Common Measurement Mistakes to Avoid

Learn from others and ensure a perfect fit

Measuring Only Once

Always measure at multiple points. Windows are rarely perfectly square. Measuring only at one height or width can result in a shade that does not fit.

Using a Cloth Tape

Cloth measuring tapes can stretch and provide inaccurate readings. Always use a steel measuring tape for window measurements.

Rounding Measurements

Record exact measurements to the nearest 1/8 inch. Rounding up or down can result in a shade that is too tight or too loose.

Ignoring Obstructions

Failing to account for handles, cranks, locks, or tile that projects into the window opening can prevent proper installation.

Measurement FAQs

No—provide your exact measurements. We make appropriate deductions (typically 1/8 inch per side, 1/4 inch total width) during manufacturing to ensure proper clearance and smooth operation. Telling us your exact window opening size allows us to make precise deductions.