Skip to main content

A-B Measuring for Free-Form Pool Covers

The A-B measuring system records the unique curves and features of a free-form pool to within about an inch. Follow the illustrated steps below, then send us your completed layout for review.

Questions before you begin? Call 800-982-6966 and we will help you prepare the layout.

Free-form pool

Free-Form Pool Measuring

Compare all measuring forms ▶

Prepare Before You Measure

Print a worksheet, review the measuring tips, and watch the A-B video before marking points around the pool.

How Free-Form Covers Are Priced

  1. Find the pool size. Rotate the measured box until one side touches two points without crossing the perimeter, then set the other sides at the pool's furthest extents.
  2. Set the priced box. Add 2 feet on every side, increasing both dimensions by 4 feet.
Diagram showing a rotated pool bounded at its maximum extents by a yellow 16-by-32-foot measurement box inside an orange 20-by-36-foot pricing box

Measure Your Free-Form Pool in Five Steps

Work clockwise, keep the tape straight and tight, and record each measurement as you go.

A-B reference line positioned beside an irregular example for a free-form pool

Step 1: Establish the A-B Line

Run a straight A-B line parallel to the pool, at least 4 feet from the water's edge and at least two-thirds the length of the pool. Point A must be to the left of point B. Measure the full A-B line and record it on your A-B measuring sheet. The example line is 20 feet long. Draw your A-B line along the bottom of the pool sketch.

Measurement points marked around an irregular example for a free-form pool

Step 2: Mark the Pool Perimeter

Use chalk to mark points at the water’s edge. The spacing does not need to be even: place marks about 2 to 3 feet apart on moderate curves and about 1 foot apart on tight curves. On straight sections, place marks at corners or wherever the pool changes direction.

Perimeter measurement points numbered clockwise around an irregular example for a free-form pool

Step 3: Number Every Point Clockwise

Start near the center of the A-B line and number every chalk mark in a clockwise direction. Continue until every point around the pool has a unique number.

Tape measurements taken from point A to each numbered pool perimeter point

Step 4a: Measure from Point A

Have an assistant hold the end of the tape at point A. Working clockwise, measure from A to every numbered perimeter point and record each distance on the A-B measuring sheet.

Tape measurements taken from point B to each numbered pool perimeter point

Step 4b: Measure from Point B

Move the tape to point B. Working clockwise again, measure from B to every numbered perimeter point and record each distance beside the matching A measurement.

Diagonal cross-check measurements drawn across an irregular example for a free-form pool

Step 5: Add Cross-Check Dimensions

Add 2 or 3 diagonal measurements between numbered points and record them on the A-B measuring sheet. Also mark stairs, rocks, walls, or other deck features within 2 feet of the water's edge so we can account for possible cover interference.

Ready to Send Your Free-Form Layout?

Enter your A-B measurements and comments online so our team can review the layout for your custom pool cover.