When you had your gunite pool installed, did the installer tell you it would last a lifetime? Or, did they tell you it may need to be re-plastered every 5 to 7 years? It seems like every company has a different theory on this subject, but what most experts in gunite pool repair will tell you is that the plaster is the problem, not the gunite.
Basically, gunite is mortar that is sprayed on and because of the sand particles, it has a rough texture. Gunite pool builders us the spray-on type because it is easier to work with in getting the different forms and shapes you’ve requested. It is also less expensive.
When this surface is applied, there are two ways for it to be treated:
1). Trowel it to smooth it, then apply a multi-coat epoxy finish that usually lasts up to 15 years or longer.
2). Some pool builders will leave the surface rough, the cheapest way to go, and then use a plaster to cover up the roughness. The plaster is a lime product, and the gas, or hypoclorate, that is added to swimming pools for disinfectant along with the sulfuric acid that is meant to control algae will dissolve that plaster. As such, you will need to have your pool re-plastered every 5 to 10 years.
Another option to this type of pool repair is to ask about continuing to re-plaster your pool instead of removing the existing plaster and have an epoxy system installed. An epoxy system will last up to 20 years.