To the real estate editor: I would like to comment on a recent letter entitled "Lasting surface for swimming pools."
We service about a hundred pools a year here in Vermont, most of them with a painted surface and maybe 15 percent with a marcite or plaster finish.
In my 20 years' experience, the usual causes of peeling paint in swimming pools in this area are improper surface preparation, use of paints not designed to be left covered with water, use of varying types of paints one over the other , too thick a paint buildup over the years, and exposure to frost.
The pools we paint every spring have either not been covered through the winter or have had an improper coating applied to the initial plaster, gunite, or poured cement surface some years earlier.
We recommend a chlorinated rubber paint manufactured by the Koppers Company, either Type A or APF, depending on the surface.
Koppers has a full line of swimming-pool paints which are designed to be left covered with water. We don't drain our pools for the winter, to avoid frost damage.
If another type of paint has been used, we match the paint type. In no way would we recommend putting one type of paint over another.
We've seen epoxy over chlorinated rubber peel off in sheets. Our experience has been that the chlorinated rubber makes a better bond with the cement surface than epoxy.
It is not unusual for a pool to go two, three, or four years without being drained and painted if it is left full of water and properly covered -- even with the deep frosts we have here in Vermont.
A plaster pool is more susceptible to staining than a pool with a painted surface. However, if the pool is properly covered so that leaves and other debris are kept out of it through the winter, and the water is chlorinated so that algae will not take hold, the chief cause left for staining is metal in the water.
This source of stains can be controlled by use of a sequestering agent.
Most reputable swimming-pool companies have a service that includes testing of the pool water and the source water; and they will recommend the proper product to use to prevent such stains. Robert H. Valeo East Dorset, Vt.