Turn down that little red dial to lower the temperature on your water heater in the summer and save on your utility bill.

Each year, thousands of Arizona residents email or call Rosie Romero’s radio show with questions about everything from preventing fires in their chimneys to getting rid of tree roots invading their sewer system. His goal is to provide answers that suit the specific lifestyle wherever someone lives in Arizona.

QUESTION: Should I set the temperature thermostat lower on my water heater in summer?

ANSWER: Yes, you can set the temperature as low as is comfortable for you. If you have an electric-powered water heater, it’s a great way to save money on your utility bill at a time when you may be running the air conditioner a lot more. You can also save turning down the dial on a gas-powered water heater.

Q: I’m taking the wood siding off my house, built in 1997, and replacing it with stucco because it doesn’t fit in with the other homes in the neighborhood. I’m doing the job myself and I’m wondering what thickness of out-sulation I need to install before putting on the stucco.

A: You don’t even need to remove that siding. You can put a Tyvek wrap around the house including the wood siding, and then put the out-sulation boards over that. Then you can apply the stucco. But there are other alternatives to stucco. For example, you can put premolded polystyrene insulation panels over the exterior of the house that allow you to install masonry units into the panels for a different kind of look.

Q: I need to remove a 20-foot saguaro from my backyard because it is infected with a disease. Have any suggestions on what to do?

A: Saguaros are native plants with state protection. According to the Arizona Department of Agriculture Web site, a landowner can destroy or remove any plant on your land. But with native saguaros, you must notify the department first. You can also sell or give away any plant on your lot. But if you’re transporting the cactus elsewhere, you need a permit and special tag. Some cities also have rules about what you can do with a saguaro.

Saguaros, of course, can become infected by bacterial necrosis. Once that happens, it’s hard to save them. If the pathogen gets into the trunk and roots, the saguaro may ooze black material out of holes on its surface. They’ll start to lean and might even fall down.

There are companies that specialize in removing saguaros. Once an infected saguaro is gone, you should remove all the root material in that area and expose the soil to sun for a year.

Q: When you’re redoing the insulation in your attic, do you need to take out all the old insulation first?

A: Generally speaking, you don’t need to do that. You can just top off the old material. Just make sure that the old insulation is not too compressed because that would reduce its effectiveness. However, if, for some reason you do need to remove it, there are companies that can remove it for you.

Q: I have a few cracks in a perimeter masonry fence that were caused by a tree and its roots. Can I caulk them to fill the cracks?

A: Yes, you can do that. The caulking won’t hold the wall together, but it will allow you to paint the wall and improve its appearance. But eventually you may have to do something about the tree.

Q: I had some oleanders that overgrew and got so big that they pushed a perimeter wall down. Now I want to replant in that area for privacy – possibly a shrub or some kind of shrubby tree. What do you recommend?

A: Mediterranean fan palms might work or Arizona rosewood or hopseed.

For more do-it-yourself tips, go to rosieonthehouse.com. An Arizona homebuilding and remodeling industry expert for 29 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) in Tucson and from 9-11 a.m. on KGVY-AM (1080) and -FM (100.7) in Green Valley. Call 888-767-4348.