Woodworker

If you're thinking about adding a swimming pool to your backyard, then chances are the cost of the project is a top concern.

Asking a local pool company how much a project will cost, however, is like asking how much a house costs to build. There's no one size-fits-all answer.

You have to factor in many elements of an in-ground pool cost, according to the Association of Pool and Spa Professionals, such as size, additions, water features, screen enclosures, heaters and patio designs.

That said, poolpricer.com gives a rough estimate of between $25,000 to $50,000 for an in-ground pool. That's a pretty big range, and even that is assuming your pool is of average size, in an average city. It also doesn't factor in the cost of your pool's upkeep.

You can, however, keep yourself informed about the many hidden costs of putting in a pool that could run up the final bill.

6 hidden costs in pool installations.

An occasional hidden cost is inevitable, and that most can and should be caught, or at least brought to light, beforehand.

Here are six hidden costs that River Pools and Spas say can derail even the best-planned pool installation budget.

- Dirt Hauling: When an in-ground swimming pool is built, a significant amount of dirt comes out of the ground and has to go somewhere. Always find out before the digging starts if dirt hauling is included in the cost of the project.

- Lawn and landscaping: The process of putting in an in-ground swimming pool requires a lot of heavy equipment. That's bad news for your manicured lawn. Any grass in this area, and perhaps on the path to the pool location, will need to be seeded or replaced after a pool installation.

- Extra Concrete: Homeowners often forget they will need patio space around the pool, which usually means more concrete. The cost of additional patio space is usually the most expensive option to the pool.

- Electrical: Some pool builders include electrical hook-up in their standard package, while others treat it as a separate invoice. The extent of an electrical job is based on how many items, such as pool lights and spas, the homeowner requests. Make sure you know where it falls on your invoice.

- Fencing: Almost every city requires a pool be behind a fence of some form. It's almost always better to have the fence addressed at the same time the swimming pool and patio are planned.

- Retaining Walls: These structures can be pricey. They also have extreme importance in terms of pool and deck stability, as well as proper yard drainage. Be sure to get the price settled before the project starts.