How to Measure Hot Tub Cover Corner Radius

The details that make it fit

Find the curve that fits your spa’s corner.

To measure a hot tub cover corner radius, extend the spa’s two straight sides to an imaginary square corner. Measure straight from that corner to where the curve meets a straight side. That distance is the radius, not the distance around the curve.

For example, if the curve meets the straight side 6 inches from the projected square corner, the corner radius is 6 inches. Use a framing square, straightedges and a tape, or the printable chart below to find yours.

Between sizes? Round the radius down.

A radius that is too large can make the cover cut across the spa’s corner and prevent a proper fit. A slightly smaller radius leaves more cover over the corner.

This guidance applies to the corner radius only. Your overall cover dimensions are the finished size we build; we do not automatically add clearance.

Method 1

Measure the radius with a framing square

  1. Place the square against the two straight sides beside the curved corner, as shown.
  2. Find where the corner curve ends and meets a straight side of the spa.
  3. Read the distance from the projected square corner to that point. That straight distance is the radius.

Read the measurement in inches. Do not follow the curved edge with the tape or measure diagonally across the corner.

Framing square aligned with the spa sides; radius measured from the projected corner to the end of the curve.
Figure 1. Measure the straight distance shown by the arrows.

Method 2

Measure the radius with straightedges and a tape

  1. Use straightedges, such as yardsticks or a level, to extend the straight sides toward an imaginary square corner.
  2. Measure from that projected corner to where the curve meets a straight side.
  3. Keep the tape straight and read the distance in inches. Do not measure along the curve.

This gives the same corner radius measurement as the framing square method.

A level extends a straight spa edge while a tape measures the corner radius.
Figure 2. A straightedge and tape provide the same measurement.

Check the corners before you order

Check more than one corner rather than assuming they all match. If the corners differ, the outline is unusual, or you cannot find a clear measurement, contact us before ordering.

The corner radius is only part of your cover size. You will also need the overall dimensions and skirt length for your replacement cover.

Need help getting the fit right?

Unsure about a measurement? Call 1-866-771-4897, Monday–Friday, 9 am–4 pm Eastern, or choose measuring assistance in the cover builder. Our team will contact you to help.

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