When it’s hot outside, there’s nothing better than a quick dip or extended soak in that big blue backyard tub of water known as a pool.
But it’s not always sunshine and drink sipping out there. In addition to the routine filtering, chemical monitoring, and occasional frog skimming, you have to address the fact that a pool’s underwater surfaces deteriorate over time.
Cracks invariably appear they can be caused by a chemical imbalance or by UV rays, or even by slight shifts in the soil beneath the pool. The veneer may start to peel. In turn, the cracks collect dirt and algae, and pretty soon you have what looks like a giant birdbath. It may be time to drain and resurface your pool.
Ways to Resurface a Pool
Vinyl liners and fiberglass pools
There are three types of in-ground pools—those with vinyl liners, those made from fiberglass, and those made of concrete.
Vinyl liners never need resurfacing—they are essentially a thick plastic bag housed inside a below-ground structure—but the liners usually need to be replaced after a period of five to nine years.
Costs average between $1 and $5 per square foot. Although there are sources for DIY-replacement liners, it’s a fairly complicated job that most pool owners relegate to a pro.
Fiberglass pools, like fiberglass boats, are finished with a tough, smooth coating known as gelcoat. Although long-lasting, gelcoat does degrade over time from UV and chemical exposure. Common signs of a gelcoat gone bad are chalking, cracking, discoloration, and blistering.
Unfortunately, gelcoat pool application is a factory process, so reapplication can’t easily be replicated in your backyard. Instead, there are replacement coatings—thermoplastic polymers such as polyFIBRO, made by ecoFINISH and epoxies that are used to resurface fiberglass. The pool must be completely drained and the entire surface sanded, then cleaned, before the new coating can be applied.
Epoxy and polymer cost
Although the polymer application is not your typical DIY task, epoxies are somewhat easier to apply. Costs can run from $1,500 for epoxy to $15,000 or more for the polymers, depending on the size of the pool.
The most common in-ground pools are concrete shells that have been finished with a type of Portland cement-based material, known in the pool trade as “plaster,” that seals and protects the shell. In many instances, the plaster is coated with paint, epoxy, or even fiberglass. The plaster can also serve as a substrate for tile.
Over time, the coating and/or surface of the plaster degrades, and it must be resurfaced. Depending on the region, your pool may need this treatment every ten to twenty years. First, any cracks or spalling must be repaired, then the entire pool shell must be prepped. The goal of the prep is to remove loose plaster and roughen the surface so that any new layers of plaster will bond to it. Sandblasting, chipping, and chemical surface etching are all techniques used in the prep.
Once the prep is complete, a new coating of plaster is applied if needed. This new plaster can be a type called exposed aggregate plaster, a mix of plaster and colored sand, pebbles, or glass beads. While exposed aggregate is typically considered a finished surface, plain plaster is usually covered with paint (often rubberized, acrylic, or epoxy formulas), fiberglass, or tile.
Although there are products sold for DIY replastering (www.sider-crete.com is one vendor that sells a kit that covers 60 square feet for $130), most DIY pool plaster products are meant for repairing only small areas. Based on a national average computed by homeadvisor.com, a professional replastering job will cost about $5/sq.ft. for plain plaster, and nearly double that for a polished exposed aggregate plaster.
Resurfacing a pool with paint
Of all these coatings, paint is the easiest and least expensive, but it also has the shortest lifespan—2-3 years for acrylic paint, 7-10 for epoxy, and somewhere in between the two for rubberized latex paint. Definitely DIY territory.
To repaint a pool, the plaster must be in good shape. Pros suggest that the plaster surface be prepped with a wash of muriatic acid followed by a rinse with TSP (trisodium phosphate) and water. (Note: Exercise extreme caution when using muriatic acid and TSP and always follow manufacturers’ instructions.) Also, the old paint must be compatible with the new paint. For instance, rubberized latex paint won’t adhere to epoxy and vice versa.
How much do pool paints cost?
If you don’t know what the old paint is, you can scrape off a few chips and have them tested at a local paint store or send them out to a manufacturer such as Ramuc. Pool paints start at about $50 per gallon for acrylics and about $100 a gallon or more for epoxy. A gallon should yield one coat of 100 square feet.
Applying fiberglass over plaster
Although it’s used to construct pools, sometimes fiberglass is also used to resurface concrete ones. Theoretically, fiberglass should be superior to plaster because it’s waterproof, so it withstands stains, has a very smooth texture, and is available in many colors.
How much does resurfacing with fiberglass cost?
If applied by an experienced installer, fiberglass does seem to make a good choice. But consumers and pros alike have voiced their dislike of its use, mostly due to improper or shoddy installation. Resurfacing with fiberglass costs between $5 and $7/sq.ft.
Tile—elegant, long-lasting, and expensive
It’s common to see tile used as a border at a pool’s waterline, but ceramic, porcelain, stone, or glass tile can be installed over the entire pool surface, in every imaginable design. Applied over the plaster, tile is installed in much the same way as it is in a bathroom: mats of small tile or larger individual tiles are glued to the plaster substrate with thinset.
When the thinset is dry, the tiles are grouted. Installing tile is a reasonable DIY project, but in a pool, the substrate plaster must be in perfect condition before you can tile, so you might have to partner up with a professional to rectify any plaster issues.
How much does it cost to retile a pool?
Material costs for tile run from about $4/sq.ft. for ceramics to $7-$50/sq.ft. and up for stone or glass tile. Add to that the cost of installation and the total price can shoot up into the realm of six figures.
The good news is that once tiled, the pool won’t need resurfacing for at least twenty years, and with proper upkeep, probably a lot longer.
Start with research
The internet is chock full of information on all things pool-ish, but the ratio of marketing jargon to understandable info is higher than one might hope for. If you’re researching pool costs, a good place to start is Homeadvisor or porch.com.
For independent pool information on design, installation, and maintenance that’s clear, concise, and encyclopedic, check out poolresearch.com.