Detailed illustrated guide

How to Measure for Custom Curtains

Measure the hardware the curtain will hang from—not only the glass. Read the complete guide once, then measure each window twice and keep the record.

Straight-on view of a complete sash window, full curtain pole with three brackets, and two open curtain panels

A correct installation has a level, fully supported pole, clear side stack-back and an unobstructed floor-length drop.

Before you start

Use a metal tape
Cloth tapes can stretch and soft tapes can sag.

Measure every window
Similar-looking windows can differ.

Write width first
Record as W × L and include the unit.

Do not deduct twice
Enter the complete coverage width unless the product says otherwise.

Complete curtain pole with both finials, three visible support brackets and open curtains stacked outside the window glassExact pole height and side-extension measurement points
01 · IF HARDWARE IS NOT INSTALLED

Plan the pole or track position

Choose the hardware position before ordering. A common starting range is 15–25 cm (6–10 in) above the frame, or close to the ceiling when proportions allow. Extend the hardware 15–38 cm (6–15 in) beyond each side to create stack-back space and reveal more glass when open.

  • Check solid fixing points, brackets, trim, vents and adjacent walls.
  • Allow more side space for thick fabric, lining or wide openings.
  • For a ceiling track, confirm the ceiling is level and suitable for fixing.
Planning width: window/frame width + left extension + right extension.
Open curtains stacked beside the glass rather than covering it
02 · PLAN OPENING SPACE

Allow for stack-back

Stack-back is the width occupied by the open curtain. It depends on fabric thickness, lining, heading, fullness and total curtain width. Use the wall extension as usable parking space; do not promise that every fold will clear the glass.

Check handles, radiators, doors and furniture. A centre-opening pair needs stack space on both sides; a single panel needs one larger clear side.

Eyelet on a pole, pleat on rings and wave heading on a track
03 · CHOOSE BEFORE MEASURING DROP

Confirm heading and hardware

The heading determines both compatibility and the vertical starting point.

  • Eyelet / rod pocket: decorative pole only; measure from the pole top.
  • Pencil / pinch pleat: pole with rings or compatible track; measure from the ring bottom or hook position.
  • Wave: compatible wave track; use the track/product reference point.

See the full heading compatibility guide →

Arrow showing usable pole width between finials
04 · WIDTH

Measure complete coverage width

Installed pole: measure the straight usable length between the finials. Do not include decorative end pieces.

Installed track: measure the usable track from end stop to end stop; include any centre overlap that is part of the system.

Planned hardware: use the planned bracket-to-bracket or track coverage width. Do not order from glass width alone.

Complete coverage width= usable pole or track width
Vertical arrow from curtain hanging point to floor
05 · DROP

Measure at left, centre and right

From the correct heading start point, measure to the floor at three positions. Floors and hardware are not always level. For a float or kiss finish, use the shortest reliable measurement unless a professional has planned individual lengths.

  • Keep the tape vertical.
  • Do not follow the wall or skirting board.
  • Repeat the measurement and record the unit.
Real linen curtain hems shown floating above, kissing and puddling on the floor
06 · FINISHED LENGTH

Choose the floor relationship

Float about 1 cm abovePractical for daily use and uneven floors.

Kiss the floorPrecise tailored result; measurement must be exact.

5 cm puddleSoft decorative finish; needs more care and floor clearance.

Finished drop= measured top-to-floor + finish adjustment
Real curtains comparing one panel, split panels, low fullness and balanced fullness
07 · PANELS & FULLNESS

Use the correct width rule

Flat/gathered headings: total fabric width ≈ coverage width × chosen fullness, then divide by panel quantity.

Made pleats: order finished panel width to cover the pole/track; construction fullness is built into the sewn pleats.

Wave: order finished coverage width for the compatible track; system fullness is built into the fold spacing.

For a split pair, enter the complete coverage width. Do not divide it unless the product page explicitly requests per-panel width.
Final checklist for heading, width, drop, panels, lining and hem
08 · FINAL CHECK

Review before ordering

  • Window/room name and units
  • Heading and compatible hardware
  • Complete usable width
  • Left, centre and right drop
  • Floor finish and finished drop
  • Single or split panels
  • Fullness/pleat construction and lining

Open the Measurement Assistant

Stop and ask for help when: the window is bay-shaped, angled, very wide, layered, above stairs, blocked by furniture, or the floor/ceiling differs substantially across the opening. Send support clear front and side photographs with the intended hardware position.