Do pool research before splashing the cash

Camp Morrier is back in business for the season. That's what friends and neighbors call Lori and John Morrier's Walpole home, which includes a 30-foot in-ground vinyl-lined pool, swing set, and grassy backyard. The 8-feet-deep pool is the center of activity, especially on hot summer days.

With an estimated 7 million residential swimming pools in the United States, recent sales have been declining because of a slow down in the housing market, according to PK Data. But for homeowners who can afford them , free-form resort-style pools continue to be popular. And in middle-class areas like the Morriers', families with children are still finding pools to be a welcome addition.

"There are seven pools just on our block," said Lori Morrier, who said that her pool provides hours of entertainment and exercise for her two children, Emily, 7, and Andrew, 11.

Adding a pool to your home should not be an impulse decision; it requires time and research, said Penny Johnson, chairwoman of the Association of Pool and Spa Professionals, a Virginia-based trade group. The typical homeowner doesn't think of adding a pool until the heat of the season, said Johnson.

"Then all of a sudden," she said, "it's 'I have $30,000, I'm going to get a swimming pool.' "

Above-ground pools, which can start at $1,000, are typically inflatable or have metal or wooden walls. These are not permanent structures and are a quick "cash and carry proposition," said Johnson. The more durable in-ground pools, $10,000 and up, must be installed by a pool builder. Of the three basic types, vinyl-lined, fiberglass, or Gunite (a type of concrete and plaster), vinyl is the most economical and adaptive to New England's harsh climate. Fiberglass, one-piece molds that are delivered to the site and placed in a hole have the fastest set up, while Gunite offers the most design flexibility. Installation can range from five days to four weeks or more. Plan on excavation and construction of the steel wall or other reinforcement; placing of the interior liner or surface; integrating the electrical and plumbing; adding water and balancing the chemicals; and landscaping.

Even if you move into a house that already has a pool, "it's not all about fun; it's a lot of work and responsibility," said Boston College varsity swim coach Tom Groden, who has a 1918 pool in the backyard of his Walpole house. The 20-by-50 pool is 4 to 8 feet deep and made of concrete. It "is functional, but not fancy. But fancy doesn't make things better in terms of what you want."

Add-on features are what increase the base price of a pool, said Johnson. These can range from heaters (practically a must in the Northeast), fiber optic lighting, digital controls, in-floor cleaning systems, sound systems, decking, and more. The more expensive Gunite pools, which usually cost 20 percent more than vinyl-lined, offer customized options such as waterfalls, shallow beach-style bathing areas, and grottos. Zero waterline pools (water level is level with the deck) and vanishing edge pools (water appears to drop off into nowhere) are the latest chic designs.

And then there are all the necessary accessories, including pumps, water filters, chemical feeders, drains, returns, and related plumbing. "My job is cabana boy," said Lori Morrier, who has a daily routine of skimming, adding chemicals, and monitoring the self-cleaning Aquabot, which, she said, "is like a family pet."

But most of all, when planning a pool, it's all about safety, said Groden. State and municipal regulations will mandate fencing, placement of pool, and filtration systems, "but only you can ensure that it is used wisely and safely," he said.