Tips on How to Paint your Pool in Hot Weather

For Concrete Or Plaster

Before noon , all concrete structures as well as plaster surfaces are exhaling air (which may contain a varying degree of moisture) as the surface is being warmed up by the sun. If chlorinated rubber is applied before the concrete is warmed up , it may skin over before the air has had a chance to escape. As the air is gradually warmed by the sun, it will expand and cause the coating to blister if it cannot escape. Whenever trouble is experienced along these lines, the painting should be deferred until the heat of the day has passed and the concrete is starting to cool off. At this point the structure is inhaling air and the danger of any blisters developing is at a minimum.

Pool Paints contain relatively quick-evaporating solvents. However, whenever the paint is applied to a surface exposed to a hot sun, a skin forms on the surface of the paint before the solvents have had an opportunity to evaporate. Thus, the trapped solvents form gases which, expands, causing bubbles and/or blisters to appear.

It should be kept in mind that the temperatures inside an empty pool will be as much as 10-15 degrees warmer than the air.

If the blisters form while painting, the best way to deal with them is to paint them over lightly with a brush dipped in thinner. This will make the blisters collapse by dissolving the paint and cause it to penetrate deeper into the pores. Blisters that are several days old should be scraped off the bare concrete and touched up with a thin priming coat. Chlorinated rubber may be thinned as much as 50%.

A certain amount of solvent evaporates from the paint during application. Care should be taken to maintain the original consistency of chlorinated rubber by the addition of thinner as the work progresses. The more heavily the material is applied, the more blisters are apt to occur. On the other hand, the material should not be thinned out excessively. Three thin coats are easier to apply in hot weather than two coats at the normal consistency. Each new coat partly dissolves the last one and then skins over rapidly, imprisoning solvents and air. Consequently, the thicker the coating, the more time is required for the imprisoned solvents to evaporate.

To Summarize:

• paint when surface is warm, not hot.
• Hot is over 90 degrees.
• Surface temperature is usually warmer than air.
• Solvent blisters occur when gases are trapped by over-application or when the surface is too hot.
• Brush lightly with thinner if blisters form while painting.
• Dried blisters can be scraped off and touched up with thinned paint.
• Apply thin coats of paint; the thicker the solvent based paint, the more time it takes to evaporate the solvents.