How to Measure a Hot Tub Spa Cover the Right Way

Ordering a replacement spa cover should not involve guesswork.

The #1 reason customers receive the wrong cover size is simple:

They measure the old cover instead of the spa shell.

This guide will show you exactly how to measure your hot tub correctly so your new cover fits perfectly the first time.

Step 1: Measure the Spa Shell — NOT the Old Cover

Over time, foam cores absorb moisture and expand. Covers sag. Vinyl stretches.

If you measure the old cover, your new one may not fit properly.

Always measure the hard acrylic shell of the spa itself.

Use a rigid tape measure and measure from outer edge to outer edge.

Step 2: Measure Length (A)

Measure the longest side of the spa from edge to edge.

Round to the nearest half inch.

Example: 83 ¾" becomes 84".

Step 3: Measure Width (B)

Measure the shorter side from edge to edge.

Again, measure the shell — not the cover.

Round to the nearest half inch.

Step 4: Measure the Corner Radius (C)

This is the most commonly measured incorrectly.

To measure radius:

1. Place a framing square or straight edge against the corner.

2. Measure from where the curve begins on each side.

3. The distance where both measurements meet is your radius.

Common radiuses:
• 2"
• 4"
• 6"
• 8"
• 11"

If unsure, send us a photo of the corner and we’ll confirm.

Step 5: Determine Skirt Length

The skirt is the vinyl flap that hangs down around the edge.

Standard skirt length is 4".

Measure from the bottom of the cover seam to the bottom of the skirt.

Most customers keep the same skirt length unless the original was incorrect.

Step 6: Confirm Hinge Direction

Your cover folds in half.

Make sure you know which direction the hinge runs:
• Front to back
• Left to right

This matters for lifter compatibility.

⚠️ Common Measuring Mistakes

❌ Measuring the old cover
❌ Forgetting to round correctly
❌ Guessing the corner radius
❌ Ignoring hinge direction
❌ Measuring the cabinet instead of the shell

Avoid these and your cover will fit perfectly.

? Pro Tip from David the Cover Czar

If you're unsure about radius or measurements:

Take a clear overhead photo of your spa and call us at 615-982-0395.

We’d rather double-check than ship the wrong size.

? Ready to Order?

You can shop your custom replacement spa cover by:

• Brand
• Exact size
• Shape

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