A gunite or shotcrete pool can last 50 years, but the plaster skin protecting it wears out in 10 to 15. Concrete pool resurfacing is the process of stripping that aged surface and applying a fresh waterproof finish, transforming a rough, stained, leaking shell back into a smooth, watertight pool. Done right, resurfacing extends the structure’s life by another decade-plus and dramatically improves how the pool looks and feels underfoot. Done late, you risk shell damage that turns a routine refinish into a major repair.
Signs Your Pool Needs Resurfacing
Concrete pools telegraph their decline well before failure. Watch for these warning signs.
- Rough or chalky plaster that scrapes feet and snags swimsuits.
- Persistent staining that returns within days of an acid wash.
- Surface cracks or spider checks spreading across the finish.
- Exposed aggregate where the plaster has eroded down to the gunite.
- Rising water bills or a dropping water line, signaling leaks through worn plaster.
- Plaster delamination, hollow-sounding spots where the coat is separating from the shell.
If you can rub your hand along the wall and pick up a cloud of white residue, the finish is breaking down. Most pools need refinishing every 10 to 15 years depending on water chemistry and climate.
The Resurfacing Process Step by Step
A professional crew typically completes the job in five to ten days, weather permitting.
- Drain and prep. The pool is fully drained and the old surface is chipped or sandblasted off, sometimes down to bare gunite for severe wear.
- Repair the shell. Cracks are routed and filled, hollow spots are cut out, and any structural issues get addressed before refinishing.
- Apply a bond coat. A scratch coat or bonding agent ensures the new finish adheres tightly.
- Trowel the new surface. Plaster, aggregate, or a quartz blend is applied and hand-troweled smooth, usually a half-inch thick.
- Acid wash and fill. The cured surface is acid-washed, then the pool is refilled slowly, often over 24 to 48 hours.
- Start-up chemistry. A careful 28-day water balancing period lets the new finish cure properly.
Finish Options and What They Cost
Your finish choice drives both the price and the lifespan.
Standard White Plaster
The classic and cheapest option at roughly $4 to $6 per square foot. It lasts 7 to 12 years and shows stains more readily.
Quartz Aggregate
Plaster blended with quartz crystals runs $5 to $8 per square foot, resists etching better, and lasts 10 to 15 years with a slightly textured look.
Pebble Finishes
Premium pebble surfaces like Pebble Tec cost $8 to $14 per square foot and can last 15 to 25 years. They hide stains, resist chemicals, and give a natural, river-bottom appearance.
Total Project Cost
For an average 16-by-32-foot pool with around 1,000 square feet of interior surface, expect a complete resurfacing to run $5,000 to $13,000 depending on finish and shell repairs. Plaster jobs land at the low end; pebble and exposed-aggregate finishes push toward the top. Tile band replacement, new coping, or extensive crack repair add to the total. Always get itemized bids from at least three licensed pool contractors.
Maintenance That Extends the Finish
The fastest way to ruin a new surface is bad water chemistry. Keep pH between 7.4 and 7.6, alkalinity at 80 to 120 ppm, and calcium hardness at 200 to 400 ppm. Low calcium water is “hungry” and leaches material right out of fresh plaster.
Brush the walls weekly for the first month, run the pump consistently during start-up, and avoid dumping shock directly onto the finish. With balanced water and routine brushing, even mid-grade plaster comfortably reaches its full service life.
How Long the Process Takes
Timeline expectations help you plan around the disruption. From the day the crew arrives to the day you can swim, a typical resurfacing spans seven to fourteen days. Draining and chipping out the old surface takes one to two days, shell repairs another day or two depending on severity, and the new finish goes on in a single intensive day of troweling.
After application, the pool sits empty briefly before the acid wash, then refilling begins immediately to keep the fresh plaster from drying out unevenly. Refilling a standard residential pool takes 24 to 48 hours of continuous water flow. Plan for cooler, dry weather if possible, since rain and freezing temperatures during curing can compromise the finish.
Resurfacing Versus Replastering Versus Replacement
These terms get used loosely, so it helps to know the difference. Replastering specifically means applying a new plaster coat, the most common form of resurfacing. Resurfacing is the broader term covering any new interior finish, whether plaster, quartz, or pebble. Full replacement, tearing out and rebuilding the shell, is rarely necessary and runs $30,000 or more.
- Resurfacing is right when the shell is sound but the finish is worn, stained, or rough.
- Spot repairs make sense for isolated cracks or small hollow areas if the rest is healthy.
- Full replacement is reserved for structural failure, major shell cracking, or extensive shifting.
For the vast majority of aging concrete pools, a quality resurfacing job restores the pool completely at a fraction of replacement cost.
DIY or Hire a Pro?
Resurfacing is one of the few pool jobs best left to specialists. Plaster has a short working time, troweling demands skill, and a botched application can delaminate within a season. The material savings from DIY rarely offset the risk of redoing the entire pool. A professional crew also brings the mixers, sprayers, and finishing tools that produce a smooth, even surface no hand tool can match.
Hire an experienced crew, choose a finish matched to your budget and climate, and your concrete pool will stay smooth and watertight for the next fifteen years. Ask for references, confirm the contractor is licensed and insured, and get the warranty terms in writing before work begins. A well-executed resurfacing is one of the best investments you can make in a concrete pool, protecting the structure while transforming how it looks and feels.
