Every year, thousands of Arizona residents email Rosie Romero's website or call his radio show with questions about everything from how to prevent fires in their chimneys to what to do about the tree roots invading their sewer systems. One of his goals is to provide answers that suit the specific lifestyle wherever someone lives in Arizona. In this column, he focuses on questions about home maintenance and improvement in the Tucson area.

Q: I want to replace the carpet in our large master bedroom, about 21 by 24 feet. The adjoining floors are ceramic tile. What are the pros and cons of wood versus wood laminate in Arizona?

A: You actually have three choices: solid hardwood, engineered hardwood and laminate flooring.

Like most people, I love the warmth and beauty of solid hardwood. Genuine hardwood floors are made from three-quarter-inch strips of solid wood and are generally the most expensive choice.

Solid hardwood expands and contracts with the changes in humidity and is sensitive to moisture; so it can't be installed directly over a concrete slab as is found in many Arizona homes. It also has to be nailed in; so you will have to install a subfloor if your house has a concrete slab. But solid wood has a protective finish that can last for 10 or more years. It can be sanded and refinished up to 10 times over its lifetime.

Engineered hardwood is a favorite of Arizona remodelers. This is made from three to five thin layers of wood laminated into one plank; the top layer is solid wood.

Engineered floors can be nailed, stapled, glued or even floated over most subfloors, including concrete slabs. You cannot sand it down and refinish it more than a couple of times. We recommend that you select an engineered floor with a top layer that is no thinner than one-eighth of an inch. This costs slightly more.

The least-expensive choice is laminate flooring; it looks like wood and can keep its finish longer than real wood. Laminate is made from processed wood chips that have been ground to dust. The wood fibers are mingled with resins, and the product is impregnated with melamine. The top layer resists scratches, dents, and wear and tear.

You don't have to nail laminate to the subfloor; it is glued down or it "floats." But the floor that you are finishing must be level. Laminate can also make a hollow-sounding noise when you walk on it. If you damage a laminate plank, it's not easy to repair.

Q: How can I get the calcium off the tiles in my swimming pool?

A: As you probably know, Arizona has very hard water loaded with calcium that can build up on surfaces like ceramic tile. You can work on those white deposits with a vinegar-and-water mixture and a scrub brush, but the results probably won't be satisfactory. The chemicals you put in your pool go a long way toward maintaining your pool's finishing materials. But over time, high levels of calcium can build up in the water.

Try having your water tested. If the levels of total dissolved solids are high, your pool may need draining and refilling with clean water that will respond to chemicals put into the pool. When the pool is drained, you can have it acid-washed to clean the surface and tile to remove any calcium residue and those white rings.

Q: Over the weekend you mentioned on your show that you should never exceed R-38 insulation in your attic in Arizona, but you didn't say why. Isn't more always better?

A: The answer is simple: Once you exceed R-38, the results versus the costs diminish greatly. So basically, it's just not worth the money. It's not a bad thing to exceed; it's just unnecessary.

The R-value, by the way, is a measure of thermal resistance; the higher the R-value, the greater the insulating effectiveness.

You can get more information about which kind of insulation works best on the U.S. Department of Energy website. You can put in the first three digits of your ZIP code to find out the insulation recommendations for various parts of your home in your area. R-38 is the recommended level for attic space in existing wood-framed homes in Tucson that have air conditioning and a natural-gas furnace, for example.

For more do-it-yourself tips, go to rosieonthehouse.com An Arizona homebuilding and remodeling industry expert for 25 years, Rosie Romero is the host of the syndicated Saturday morning "Rosie on the House" radio program, heard locally from 8-11 a.m. on KNST-AM (790) and -FM (97.1) in Tucson and KGVY-AM (1080) and -FM (100.7) in Green Valley. Call 1-888-767-4348.