Why Pool Plaster Gets Rough & How It’s Professionally Restored

Why Pool Plaster Gets Rough and How Professionals Fix It

Pool plaster starts its life as a smooth, inviting surface — but over time, it can develop rough, gritty, or sandpaper-like textures. This isn’t just a comfort issue; it’s a signal that the plaster is undergoing chemical, mechanical, or age-related wear. Understanding why this happens and how it’s corrected can help pool owners protect their investment.

Common Causes of Rough Pool Plaster

1. Water Chemistry Imbalances

Water balance is the single most important factor in plaster longevity.

• Low pH or alkalinity creates corrosive water that dissolves calcium from the plaster’s surface, causing etching and pitting.
• High calcium hardness promotes calcium scale deposits that feel hard and abrasive.

2. Aggressive Cleaning Practices

• Overuse of acid washes strips away the smooth cement paste, exposing coarse aggregates beneath.
• Improper brushing techniques on fresh plaster can disrupt curing and leave micro-rough spots.

3. Saltwater Effects

Saltwater pools are popular for their gentle feel, but salt can accelerate the breakdown of plaster if water chemistry is neglected.

4. Installation or Curing Issues

• Incorrect troweling, improper mixing, or rushed filling can leave the surface uneven.
• Poor curing conditions can lead to soft spots that erode quickly.

5. Natural Aging

Even perfectly applied and maintained plaster wears down. Standard white plaster often lasts 5–10 years, while quartz and pebble finishes may last longer but eventually lose their original smoothness.

6. New Plaster Dust

Freshly plastered pools produce plaster dust during the curing period. If not brushed away and chemically managed, this dust can harden into rough deposits.

Professional Methods for Restoring Smoothness

1. Balancing the Water Chemistry

Before any physical work begins, water parameters are corrected to stop ongoing damage. Target ranges include:

• pH: 7.2–7.6
• Total Alkalinity: 80–120 ppm
• Calcium Hardness: 200–400 ppm

Keeping water within these ranges prevents new scale and minimizes further etching.

2. Controlled Acid Washing

A mild acid wash can remove surface scale and staining, revealing smoother plaster underneath. This must be done with precision to avoid over-exposing the aggregate.

3. Diamond Pad Polishing

One of the most effective modern techniques is wet polishing with diamond abrasive pads:

• Step 1: Coarse grit (50–70) to remove high points and calcium nodules.
• Step 2: Medium to fine grit (100–120) to refine texture.
• Pads are resin-bonded and non-corrosive, ensuring no metal particles cause staining.
  This method smooths the plaster without significantly reducing its thickness, extending the surface’s lifespan.

4. Spot Repairs

For localized damage, small areas can be patched or sanded without resurfacing the entire pool.

5. Complete Replastering

If the plaster is beyond repair — deeply etched, soft, or thin — a new layer is applied after preparing and bonding to the old surface. Proper curing and balanced water chemistry are critical to ensure the new finish lasts.

Prevention Tips for Long-Lasting Smooth Plaster

• Test and balance water chemistry weekly.
• Use a quality sequestering agent to prevent scale.
• Avoid unnecessary acid washes.
• Brush new plaster daily for the first month.
• Keep salt levels within manufacturer recommendations.

In Summary:

Rough pool plaster is a common problem caused by chemistry issues, physical wear, and natural aging. The good news is that in many cases, the surface can be restored without the cost of full replastering. By understanding the causes and solutions, pool owners can make informed decisions and keep their pools comfortable and inviting for years.