Measuring your pool correctly for a cover is the single most important step in ensuring a proper fit, long-term durability, and optimal performance. An inaccurate measurement leads to a cover that is difficult to handle, inefficient at heating the water, and prone to tearing under stress. This guide walks you through the precise process, from gathering the right tools to understanding specific pool geometries, so you can order a cover with confidence.
Gathering the Essential Measuring Tools
Before you begin, you must assemble the correct equipment to avoid errors. Relying on a flexible fabric tape measure alone can lead to sagging or incorrect readings, especially over long distances. You need a rigid 100-foot metal tape measure for straight lines, a notepad and waterproof marker to record dimensions, and possibly a piece of string for complex curves. Additionally, having a second person is highly recommended; one person can hold the tape securely at the starting point while the other retrieves measurements, ensuring the tape remains taut and level.
Basic Rectangular and Square Pools
For the most common pool shapes, the measurement process is straightforward and relies on calculating the surface area. You will need to determine the length and width of the pool's overall structure, including the coping or deck area the cover must encapsulate. Record these two dimensions precisely. To determine the total cover size, simply multiply the length by the width. For example, a pool that measures 20 feet by 40 feet requires a cover with a minimum base dimension of 20' x 40', though adding a few inches to each side can aid in installation.
Accounting for Depth and Slope
Not all pools are flat-bottomed, and this variance significantly impacts the cover's final dimensions. For pools with a constant depth, a standard rectangular cover usually suffices. However, if your pool slopes significantly from the shallow end to the deep end, you must measure both the shallow and deep wall heights. A cover cut to the shallow wall height will not reach the deep end, creating gaps that allow debris to enter. Always provide the slope details to the cover manufacturer so they can create a pattern that contours correctly to the pool's geometry.
Measuring Irround and Oval Pools
Irregularly shaped pools require a different approach than standard rectangles. To measure an oval pool accurately, you must identify the longest point (the major axis) and the widest point (the minor axis). Stretch the tape measure across the pool at its longest possible point and record that number. Then, move to the perpendicular center and measure the widest point there. Because the stress distribution on an oval cover is different, providing these two critical dimensions to the manufacturer ensures the cover is reinforced properly and fits snugly without being misshapen.
Complex Shapes and Free-Form Designs
Kidney-shaped, figure-eight, or free-form pools present the greatest measurement challenge due to their non-linear contours. For these, the string method is often the most effective. Outline the entire perimeter of the waterline with a piece of string, carefully following the curve. Once the string is laid out, lift it and measure its total length with the metal tape. Additionally, measure the widest point across the shape in multiple directions. Providing the manufacturer with the string outline photo alongside these linear measurements allows for a custom pattern that follows the unique architecture of the pool.
Including Overlap and Hardware
Simply measuring the waterline is insufficient; a cover needs overlap to function correctly. Standard safety covers typically require a 2-inch overlap on all sides, while solar covers often need a 12 to 18-inch overlap to ensure proper suction and alignment. Furthermore, you must account for the placement of anchors, lift loops, and any steps leading into the pool. If you have a deep end, the cover material must be long enough to drape over the top edge and reach the bottom shelf where the anchor bolts are located. Neglecting these factors results in a cover that pulls out of place or cannot be secured properly.
Safety Considerations and Final Verification
When submitting measurements to a manufacturer, clarity is paramount. Always specify whether your dimensions are to the waterline or to the top of the coping. Include notes regarding unusual slopes, deep steps, or benches within the pool floor. Before finalizing the order, verify the measurements by recalculating the area and cross-checking the width against the length. A reputable cover supplier will review your dimensions and may contact you for clarification; this professional interaction is a sign of quality service and helps prevent costly mistakes that lead to ill-fitting covers.
