Plan a Pool

Before a pool is a construction project, it's a planning one. Long before anyone digs, the questions are arithmetic: how much water it holds, how long the hose takes to fill it, how much of the shell is tiled, and where the top-up water comes from. Those numbers shape the decisions — a pool's volume drives everything from filtration to heating to how you treat it, so it's worth getting right at the kitchen-table stage.

The method is simple when you know it: surface area times average depth, with the average handling the sloped floor most pools have. From volume come litres and gallons, fill time from a measured hose flow, and a sense of the water mass involved — a modest pool is a small lake in tonnes. This hub sequences those numbers, adds the tile takeoff for waterlines and full finishes, and borrows the pond calculator for anyone weighing a natural-pool alternative.

The honesty comes early here: pools are regulated, and not loosely. Barriers and gates are set by law in most countries, and water treatment is a chemical-handling discipline that follows product instructions and professional guidance — not a calculator. The sections below say where the planning stops and the professionals start.

1. Fix the size and position. Footprint, sunlight, overhanging trees and machinery access — and the local setback rules, which vary by area and can rule out half the garden before any maths starts.
2. Work out the volume. Surface area times average depth for a sloped floor — a 1.2 m shallow end and 2.0 m deep end average to 1.6 m. That single number becomes litres, gallons, fill time and water mass.
3. Think through the excavation. The hole is always bigger than the pool: the cut needs working space around the shell, and sides are often battered or benched for safety — so as a planning concept, excavation volume runs at the pool volume plus working space. It's a concept, not a formula: the digger driver and ground conditions decide the real number.
4. Total the finishes. Waterline tiles or a full tiled finish are area jobs — surface strip or shell area, with waste by pattern and cuts at fittings and corners.
5. Respect the treatment line. Filtration, circulation rates and chemical treatment follow equipment specifications, product instructions and professional guidance. This site calculates volume only — it does not dose chemicals.
6. Plan the top-ups. Evaporation and backwashing mean the pool drinks water all season, and rain can give some of it back — the rainwater calculator frames how much a roof harvests per event.
7. Design the barrier in, not on. Fencing, gate latching and what counts as climbable are legal requirements in most countries — settle them before the layout is fixed, not after.