Selecting and applying coating products
By Kevin Harrington, RAMUC Pool Coatings
Painting is one of the best ways to protect and beautify both commercial and residential pools. In addition to adding a vibrant, fresh color, a new coat of paint can be a cost-efficient way to give new life to concrete, plaster or fiberglass pool surfaces. Proper planning, surface preparation and using best practices from the field will help ensure the best results.
Types of Pool Coatings
There are three types of coatings that are suitable for aquatic surfaces:
This paint can be applied over most types of coatings, providing they are in sound condition. Additionally, water-based acrylic paint can be used on damp surfaces. This is a cost-efficient painting approach and, when done correctly, may last up to two seasons.
Chlorinated or synthetic rubber
Lasting up to five years, chlorinated rubber coatings provide excellent protection and coverage for previously painted chlorinated rubber surfaces like bare concrete, marcite or plaster.
Synthetic rubber coatings can be applied over existing chlorinated or synthetic rubber systems, bare concrete, or plaster and is intended for use where adherence to volatile organic compound (VOC) regulations is required. When properly applied, this finish can last up to three years.
Both of these coating systems can also be used for fountains and ponds.
This paint option creates a tough, durable finish with stain, chemical and abrasion resistance. Epoxy can be an excellent alternative to replastering; two coats of a high-build epoxy will achieve a hard, abrasion-resistant surface that costs one-third less than expensive resurfacing finishes. With proper preparation, a high-build epoxy finish can last up to eight years. Traditional epoxy will last approximately five years.
Remember to also consider self-priming paints that will reduce the amount of time needed to complete the job and save money by avoiding the purchase of a primer.
Pro Tip: Always check into the VOC regulations where the pool is being painted before purchasing a coating product, as regulations vary in Canada and the United States.
Paint selection begins by determining what type of coating is currently on the pool. Unfortunately, pools can have many, many layers of built-up paint of varying types.
To prevent an expensive mistake, a paint chip should be sent to the paint supplier for analysis, as they can provide information such as thickness, number of coats present and integrity of adhesion — as well as make recommendations for the best paint to use in the particular pool application. Always select the same type of coating to ensure compatibility.
Pro Tip: Some plaster surfaces that show signs of serious deterioration should be resurfaced first, before painting. Acute flaking, chipping or peeling may indicate a surface that is soon to fail. If the surface is not suitable, the paint will peel and remove the plaster with it.
Inspect and Prepare the Pool Surface
Once the best type of paint to use on the pool is determined, the next step is to carefully inspect the pool surface and repair any minor damage. Whatever type of coating is being used, it will adhere best to a solid and clean surface. To do this properly, the following steps must be taken:
- Drain the pool and allow it to dry.
- Clear away any debris left on the bottom.
- Visually inspect the empty pool, scanning for peeling paint, cracks, chips or surface defects.
- Scrape any defects and sand smooth.
- Repair any minor cracks or chips. A structural engineer should be consulted if any major cracks or surface defects are found. These areas should be thoroughly investigated, as they may compromise the integrity of the pool.
There are products designed specifically for pool surface preparation and using them is highly recommended. Pool professionals who are not using a specialty ‘clean and prep’ product should use this three-step process:
- Power wash the entire pool surface using a minimum 3200-psi power washer.
- Once dry, sweep or use a blower to clear away any leftover paint chips or debris.
- Use a garden sprayer to evenly apply a preparation product to the entire surface, following the manufacturer’s mixing instructions.
- Scrub the solution, which will begin to foam and etch. Continue scrubbing until the foaming stops, paying extra attention to areas where heavy soil accumulates, such as the waterline and steps.
- Flush the surface three times with a strong stream of clean water from a garden hose. Do not flush using a power washer, as it lacks the volume of water required to effectively flush the surface. It is important that all residual preparation solutions are removed.
Pro Tip: A clean, bare concrete or plaster surface that is ready for painting should have the texture of medium-grade sandpaper.
The type of coating being applied will dictate how dry the surface must be before the process can begin; check the product manufacturer’s instructions.
Moisture may still be present even if a surface looks and feels dry; therefore, pool professionals should use the following steps to test for dryness:
- Use duct tape to affix 2-square foot sheets of clear plastic to three different areas of the pool — one to the floor in the shallow end, another to the floor in the deep end and the third on a wall in the deep end that receives shade.
- After the plastic sheets have been applied, wait four to five hours.
- After the waiting period, check inside the plastic for any signs of moisture from condensation.
- If moisture is present, remove all three areas of plastic and let the surface dry for another 24 hours. Then, repeat the test.
Applying the Paint
When applying the pool coating adhere to the recommended coverage. Paint that is applied too thin will not provide adequate coverage or yield a long-lasting result; whereas too much may cause air bubbles, ‘alligatoring’ or blistering.
Pro Tip: Pool professionals should be aware of daytime and overnight temperatures for optimal painting conditions. If the temperature is above 85 F, the paint can blister. Temperatures under 50 F will cause the paint formula to become more viscous or thickened, making it difficult to apply evenly.
The chemicals that make up the paint require a specific temperature range to bond together and adhere to the surface. If the paint is not able to cure, uneven coverage, peeling, bubbling, cracking and other problems can occur.
In addition, do not paint in direct sunlight as it will affect adhesion, primarily because it causes the paint to dry too quickly. The solvents in the formula will not be able to evaporate properly and result in adhesion failure. High temperatures can cause the paint to bubble and blister, which results in peeling once it cures.
To apply pool paint correctly, it is important to use these best practices from the field:
- Sweep or use a leaf blower to clear away any remaining leaves, paint chips or debris before starting to paint.
- Use masking tape to protect any areas that are not to be painted (e.g., tiles or fittings). To avoid getting paint on larger areas, cover them with plastic and tape.
- Paint around small or hard-to-reach areas (e.g. drain openings, corners and ladders) using a paintbrush.
- Use a roller to paint larger areas, beginning with the walls.
- Once the walls are complete, move to the floor and start at the deepest section.
- Always paint toward the shallow end, and plan to finish at a ladder or stairs to exit the pool without stepping on the wet paint.
- Refer to the product recommendations to determine if a second coat is necessary. If so, allow for the proper drying time as per the product’s instructions. Then, follow the same application steps.
The time between coats of paint can get tricky on pools that are outdoors — especially if it rains between coats of paint. Rain can really slow down the process as the painting of the second coat typically needs to happen within eight to 48 hours.
Once you get beyond the 48-hour mark, the second coat may not bond to the first. When this happens, you need to roughen the surface of the first coat to get the second coat to stick. This typically has to be done manually and can be very time consuming.
Pro Tip: If rain interrupts the pool painting progress, a good rule of thumb is to add one day for the surface to dry for each day of rain.
Before refilling and opening the pool, make sure the paint is completely dry. Revisiting the moisture test may be necessary to be certain.
Proper planning, surface preparation and using best practices from the field will help ensure amazing results when painting a pool. Before embarking on the next pool painting job, take the time to get a paint chip analysis of the paint currently on the pool surface. Choose a paint that is formulated with quality raw materials and manufacturing processes to achieve the best results and complete the job successfully.
Kevin Harrington is the division manager of the Ramuc Pool Paint Company, located in Rockaway, New Jersey. A graduate of Rutgers University, Harrington has been in the coatings industry for more than 41 years. As an industry veteran, he has vast product knowledge and extensive industry experience, making him the go-to person for those seeking expertise in aquatic coatings. Harrington can be reached via email at firstname.lastname@example.org.