It's sweltering. Who can blame you if you're looking for ways to cool down?! But if that means you're thinking about building a pool, you'll want to consider the financial ramifications first.

And we're not just talking about the cost of building one, properly maintaining it, and adding it to your insurance, all of which is pricey. "The average cost in the U.S. to install, equip, and fill a 600-sq.-ft. concrete pool starts at $30,000," said Houselogic. "Add in details like safety fences (most states require them), waterfalls, lighting, landscaping, and perhaps a spa, and you're easily looking at totals approaching $100,000."

If value and return on investment are on your mind (and they definitely should be), crunching some numbers before you start digging out your yard is prudent - even if you think you're going to live in your home forever. Talking to your real estate agent, even if you have no plans of selling your home anytime soon (or ever), is also a good idea. While opinions differ - some REALTORS® will tell you that pools pay off, while others will tell you not to expect good ROI—having some knowledge of what to expect, especially in your market, will help you to make a more informed decision.

Build that pool!

Do you live in a warm-weather state, like Florida, Texas, or California? If your answer is yes, you typically have a much better chance of a decent return than, say, somewhere like Alaska. Now take a look at the type of neighborhood you live in. Does every backyard on your street have a pool but yours? You could be penalized when you go to sell by being the only home without a pool.

Architectural Digest talked to Jill Penman, an associate at One Sotheby's International Realty in Coral Gables, Florida, to get her take on must-have outdoor features that add value. "Adding a swimming pool is a 100 percent sure way to increase a home's value," she said of the Coral Gables area.

If you've decided you're going to go ahead and build it, you still have a few key decisions ahead of you, like what type of pool makes the most sense, what size it should be, what materials to use, etc.

"The biggest demand today is for pools that incorporate natural elements and appear to be part of the landscape," she added. "A free-form pool is generally more desirable than the traditional rectangular shape. And a dark interior finish, such as Diamond Brite French Gray, is preferred to cookie-cutter bright blue. Coral stone, a quarried rock that incorporates marine fossils, is a favorite for pool surrounds, copings, and tanning ledges or wet decks—wide, shallow in-pool shelves that let you cool off without venturing all the way into the water. They're very popular, as are waterfalls, fountains, and other water features."

Keep in mind, though, that, even "if all circumstances are right when it comes time to sell," said Houselogic, "that's no guarantee you'll get a return on your investment. At most, your home's value might increase 7%."

Give it a bit more thought

Are pools a novelty in your neighborhood? Will you be over-improving for your neighborhood if you build one? Will you be eating up every square inch of available outdoor space? These are just a few of the considerations before you build a pool.

What kind of neighborhood do you live in? If your neighborhood tends to attract mainly young families, you may think that having a pool could entice them…but just the opposite may be true.

"Swimming pools are nice to enjoy at a friend's or neighbor's house, but can be a hassle to have at your own home," said Investopedia. "Many potential homebuyers view swimming pools as dangerous, expensive to maintain and a lawsuit waiting to happen. Families with young children in particular may turn down an otherwise perfect house because of the pool (and the fear of a child going in the pool unsupervised)."

There are ways to increase the probability that you'll see a good return on your investment with a pool - but you won't know for sure how it will be embraced until you list your home. "Will adding a pool increase the value of your home when you decide to sell it? That's a great question, and the best answer is maybe - if you're lucky," said Dave Ramsey. Between the cost of building and the ongoing costs to keep it looking nice and functioning well, "you've got a large price tag to try to recoup when you're ready to sell your home. It won't be easy since a swimming pool can actually make your home harder to sell. Many buyers consider it a liability rather than a luxury."