If you use slate outdoors, as on this backyard bench, don't seal the tiles, as the sealer will deteriorate in intense sunshine.


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.

QUESTION: Our outside patio is covered with slate slabs, but the slate is flaking off. We previously sealed it with a sealer from a home improvement store, but that sealer peels and flakes off as well in the heat and due to the water that splashes out of our pool. What should we do about the situation?

ANSWER: Slate tiles or slabs used outdoors can look beautiful outdoors, but can present some maintenance issues. Sealers - whether they sit on top of the stone or whether they penetrate it - should not be applied to natural stone or slate used on outdoor patios as they will deteriorate quickly due to intense UV rays from the sun. As you have seen, that sunshine can cause a sealer to flake or peel off. A sealer can also trap rainwater or water from sprinklers on the surface of the stones, and that will increase flaking.

You should probably start by stripping the sealer off the slate and then leaving it unsealed, as we would suggest with a new installation. Your success with stripping may vary depending on the type of sealer you used. If some stone is too damaged by flaking, you could replace some stones in the worst areas. If none of that suits you, you could replace the patio with a more resilient option. Porcelain or ceramic tile is often used. There is even tile that has the look of slate. Other possibilities that we favor are permeable pavers or stamped concrete. Note: It is possible to seal slate and other porous stones used inside your home.

Q: I have a flat-roofed home that has insulation batting in the ceiling. An insulation company recently suggested that I could completely fill the space in the ceiling with blown-in expanding foam. Their plan also included removing all roof vents, bird boards, and so forth, and sealing up the space completely. I was taught, however, that you need airspace and venting to remove moisture from attic spaces. Has this idea changed? Is it worthwhile to completely fill up and seal the small space under a flat roof?

A: Generally, we do recommend that there be venting and air circulating above any insulation in a crawl space. That is particularly important in the Phoenix area where temperatures can be extreme, but, of course, Tucson is not quite so hot in the summer. You really should start with the building department in Tucson to find out whether you can legally do this kind of an insulation job or not, based on the construction of your home.

Then, regarding the question of whether this is a worthwhile job, you need to find out the R-rating of the insulation the company wants to put into your crawl space. If they're talking about selling you insulation that is rated at more than R-38, they are probably charging you a very high price, and your return on investment will be greatly diminished. Overinsulating your crawl space won't save you enough money on your power bills to make the expense worthwhile.

Q: I clean the home of a Tucson family weekly. It has bamboo floors that have been glued down. I use a recommended hardwood floor cleaner, but the cleaning water is always black with dirt. I change the water three times while damp mopping. Can you help me with new ideas on how to get the floors cleaner? They seem dull and lifeless. Or is that the way that bamboo is supposed to look minus the dirt?

A: Unfortunately, it doesn't sound as if there is much more that you can do about it. Flooring experts tell us that it really depends on what has made the floor dull in the first place. Perhaps there is a buildup of grime on this floor, or perhaps the finish has been scraped off. It seems unlikely that the luster of this floor will ever come back.

About the only measure that can be taken to improve the situation is to have the finish stripped off the floor and then to have the bamboo refinished. It probably will not look like new, however. So you're probably doing the best possible job with what you have to work with.

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.