Step-by-Step Guide to Preparing Your Pool for Painting

Preparation Is Most of the Job

Before you open a tin, understand this: surface preparation determines whether your pool looks good for seven years or starts peeling in one. Everything else is secondary.

The process is broadly the same for epoxy and chlorinated rubber, and it takes real effort. Here’s how to get it right.

Step 1 — Work Out What’s Already On the Pool

Do this before you buy anything. Epoxy will not adhere over chlorinated rubber, and getting it wrong means stripping the entire pool.

Rub the existing surface firmly for about a minute with a clean rag dampened in acetone or Chlorinated Rubber Solvent:

• Softens and goes sticky — chlorinated rubber. Recoat with Luxapool® Chlorinated Rubber.
• Stays firm — epoxy. Recoat with Luxapool® Epoxy.

Test several areas. Older pools are often a patchwork. Not confident? Send us a photo.

Step 2 — Drain and Inspect

Drain completely, then walk the pool and note every crack, chip, hollow spot, flaking area and algae patch. Make your repair list before you start cleaning.

On marblesheen or quartzon, go over the whole surface with a notched hammer. Anything crumbly, soft or drummy must be cut out and re-rendered — and if more than 10% of the pool is unsound, Colormaker recommend removing all of it and treating the pool as new cement.

Check the weather forecast at this point too. You need several consecutive fine days — one for preparation, more for coats — and epoxy needs 10 to 30°C holding for the hours after application. Rain during application or curing causes surface defects or outright failure.

Step 3 — Wash Thoroughly

Pool surfaces carry body fats, sun creams and oils that ordinary washing won’t shift, and those are a leading cause of paint failure.

Wash the entire surface with concentrated wash diluted at 500mL to 20L of warm water, scrubbing with a stiff brush, then rinse thoroughly. Pay particular attention to the waterline, steps, corners and any area where swimmers congregate.

Remove dirt, algae and organic growth, oils and sunscreen residue, and chemical or calcium deposits.

Step 4 — Repair Cracks and Defects

Paint will not bridge a gap. Every crack, chip and hollow spot has to be filled before you go further.

Luxapool® Structural Epoxy Filler handles most defects, and Patch & Anchor Polymer Cement suits larger patches. Let all repairs cure overnight, then sand flush.

Structural cracks — anything that looks like movement rather than surface damage — need professional assessment first.

Step 5 — Etch or Abrade

Which one depends on the surface.

Bare cement render: acid etch at 2 parts water to 1 part acid on new render, or 3 parts water to 1 part acid on old render or pebblecrete. Marblesheen takes concentrated acid if sound and hard, or 1:1 if sound but soft.

Always add acid to water, never water to acid. Work a small section at a time with a nylon broom, flush as soon as the bubbling stops — 5 to 15 minutes — and never let acid residue dry on the pool. Then neutralise with bicarbonate of soda (1kg to 10L warm water) and flush again. The etched surface should feel like sandpaper.

Fibreglass and previously painted epoxy: no etching. Instead, abrade the entire surface with 20–40 grit — sanding discs, belt sander or angle grinder — until all of it has a sandpaper feel. On fibreglass, dull the gelcoat without cutting into the laminate underneath. Water blasting is not a substitute, and a partial scuff is the most common reason a recoat peels.

Vacuum or sweep the dust, then hose thoroughly to remove the last of it.

Safety gear throughout — gloves, goggles, boots and a suitable respirator. Cutting concrete and fibreglass produces dust you don’t want to breathe.

Step 6 — Dry Completely

This one catches people out. Moisture content must be below 5% before any paint goes on.

No hygrometer? Tape a square of black plastic to the pool floor in the morning the day before painting. Lift it mid-afternoon and check the underside. Water droplets on the plastic mean the surface is still too wet to paint.

Painting over trapped moisture causes blistering and adhesion failure, sometimes months later.

Step 7 — Prime, If You Need To

Bare or uncoated cement-based surfaces — new concrete, render, marblesheen, quartzon, pebblecrete — need Luxapool® Epoxy Primer Sealer. It seals in water-soluble salts and eliminates pinholes that would otherwise blister the topcoat. Colormaker specify around 4 kits alongside 8 kits of topcoat for a standard 10m × 5m pool.

Apply it between 8am and 11am, out of direct sun, not below 10°C, and topcoat 16 to 24 hours later — not longer.

Fibreglass — no primer. The abrasion provides the key.

Sound existing epoxy — no primer, provided it’s been fully abraded. Any large patches of exposed render underneath should be etched and primed as bare surface.

Chlorinated rubber — no separate primer. The first thin coat acts as its own base.

What to Watch For

• Flaking or powdery existing paint — must come off before painting
• Efflorescence, the white salty deposit — indicates moisture movement through the substrate
• Mould, algae and organic staining
• Oil or chemical residue at the waterline
• Hollow-sounding areas, which suggest the render has lost its bond
• White calcite on fibreglass — remove with acid before abrading

Order Before You Start

Work out your quantities with the Pool Paint Calculator and order everything in one go. Epoxy shouldn’t be part-mixed and colour can vary between batches, so a top-up tin bought a week later may not match what’s already on the wall.

A 10m × 5m pool takes 8 to 10 kits over two coats. Pebblecrete takes roughly double, at three coats.