If you aren’t getting hot water out of a single-handle shower fixture, the cartridge seals inside are probably shot.

QUESTION: I have a single-handle bath and shower fixture, but I don’t have hot water anymore in the bathtub-shower area. I do have hot water in the sink faucet. How can I solve this problem?

ANSWER: The problem is that the seals inside the cartridge for the bath-shower fixture are probably worn out. To fix this problem, you’ll need to turn off the water to the house at the main shut-off valve and bleed the pressure off by opening a faucet or hose bib somewhere in the house.

Then you can remove the handle from the valve. That will expose a locking nut that you can remove along with a cover sleeve encasing the cartridge. After removing the cartridge, take it to a plumbing supply store to find replacement parts. The store can probably install the parts while you’re there. But if the entire cartridge is in bad shape, you can buy a new one to install when you get home.

Q: How do I repair the cracks in the stucco on the parapet walls on my flat roof? Someone told me to mix roof coating with sand and apply the mixture to the cracks. They said I can repaint after the mixture dries. Will this work?

A: After washing the area to remove dirt, loose or peeling paint, and chalkiness, the best method is to use elastomeric caulk to fill small cracks in stucco walls. This caulk works well because it has great elasticity. It will move with cracks if they widen and will help prevent water from seeping through cracks. After the caulk dries, you can repaint.

Q: I have a 1971 home with a cast-iron drain system that seems to be leaking from the washer drain line under the slab in my carport. A home warranty company will pay for repairs except for replacing of concrete in the carport. I’ve been quoted $750 for concrete repair. But the plumber says he doesn’t know exactly where the cast iron piping is failing. If they open the slab and see that the carport section is OK, then they may have to run piping into and possibly through the house. I’m a senior citizen with limited funds. Suggestions for a solution would be appreciated.

A: Sorry to hear about your problem. Unfortunately, cast iron does rust out over time, leaving homeowners with expensive repairs, as you are fully aware. There really aren’t great options. The plumber is right; he has no idea where the problem is. The only thing a plumber might do is send a camera down the line to see where the damage is and find the extent of the decay. That may help eliminate some other related investigation and repairs.

Q: Our Tucson house was built in 1992 and has stucco that is below the soil level. As a result, subterranean termites have gotten into the house several times behind the stucco. The top of the slab is above grade all around the house. Can the stucco be trimmed so it is above grade? If so, what type of contractor can do this? Would a weep screed be installed after we trim the stucco?

A: Stucco should not be covered with soil or any landscape ground cover. There should be at least four inches from the finished grade to the bottom of the stucco weep screed. The stucco should not be cut back. Instead the grade should be lowered to provide clearance. Those four inches allow for draining moisture that may build up in the stucco assembly and will make any termite tubes easier to see.

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.