Measurement Guide for Arch or Eyebrow Drapery Rods

How to Measure for Arch & Eyebrow Curtain Rods

Rods for arch and eyebrow windows are designed to follow the natural curve of the glass—but are mounted outside the window frame. In other words, your rod will mirror the shape of the window, just slightly offset to allow space for your drapery.

The process is simpler than it looks. We’ll guide you through it step by step.

Step 1: Measure the Window (Glass Area Only)
We start by capturing the exact shape of your window.

You’ll need two measurements:

• Width (W) – straight across the glass
• Height (H) – from where the curve begins to the top of the arch

How to Find the Height (H)
Because arches can be tricky, the easiest way to determine height is by using one of the following methods.

Take these measurements:

• A= Distance from floor at side of window to beginning of curve.
• B= Distance from side of window at beginning of curve to ceiling.
• C= Distance from floor at center of glass window to top of arch.
• D= Distance from top of arch to ceiling.

Then calculate:

H = C − A or H = B − D

✔ Both methods should give you the same height

Step 2: Choose Where the Rod Will Sit
Now that we know your window shape, the next step is deciding where you want the rod positioned relative to the window.

You need to provide the following options, and we’ll take care of the rest.

• U= Distance from the top of the arch to the underside of the rod (without rings). P= Distance from the top of the arch to the top edge of the drapery panel (for rings).
• L= Distance from the left side edge of glass to the end of rod (base of finial).
• R= Distance from the right side edge of glass to the end of rod (base of finial).

NOTE: L and R are usually the same number. If using rings, the last ring will be located approx. 1” less than the L and R, depending on the curve of the rod. The L and R distance is the straight line extension of the width, and so the rod may not come down to this location depending on the curve of the rod and the measures specified for U or P.

Helpful Tips

• Measure carefully and double-check your numbers
• Your rod will be custom-made to match your window’s curve
• We’ll adjust everything needed to ensure a proper fit

We’ll Handle the Details
Once you send your measurements, we:

• Calculate the exact curve
• Adjust for placement and projection
• Ensure everything fits beautifully and functions properly