Common pool plaster issues

What are those common pool plaster issues? And how can we fix it?

• Rebar Stains - The word “rebar” is short for reinforcement bar, a kind of steel used to reinforce and strengthen the structural foundation of the concrete. Rebar stains is a serious issue that pool owners should immediately address because those stains that we see are rusting rebar will weaken the foundation, it may look small rust but the corrosion below the plaster is larger than we think. This is the result of the rebar not being fully covered by the cement and remain exposed while the plaster is applied. How to fix it? These are different options to choose from: Drain the pool to fully expose the stain and jackhammer it to cut the rebar, then resurface it. The other one is to get rid of the exposed rebar and patch over it.

• White Soft Spotting - White soft spotting is a result of losing two soluble plaster components which are calcium chloride and calcium hydroxide. That is the reason why the surface is soft, weak, and self-deteriorating. This kind of pool plaster issue cannot be fixed. The swimming pool needs to be completely resurfaced. This is nothing to do with the pool chemicals or its water balance system.

• Nodules - Calcium nodules are white growth of hard calcium deposits and they are usually round in shape or volcano-like appearance. It is a result of not properly bonding the plaster surface to the substructure plus some defects that made the water penetrate the interior of the plaster causing to dissolve of the calcium hydroxide and becoming calcium nodules. You can fix it by sanding it off to bring back its beauty. But since it is a long-term defect, it will grow again in several months. Replastering the pool is the only solution to make it go away.

• Mottling - This discoloration is because of the high presence of calcium chloride in the plaster mix. It is also because of environmental factors like wind, sunlight - heat, humidity, and water temperature. To fix it, the experts will use high heat using a blow torch to the defect area. If it would work, resurfacing the pool is a must!