Your Place: Oxygenated bleach may help keep grout clean

Question: I'd like to know how to clean grout in the bathroom - some of it has gotten dark. Have tried different things like bleach, but it does not seem to help keep it nice in the long run.

Answer: Try oxygenated bleach (a product such as OxyClean), which is nontoxic and thus can be left sitting on the grout for a long period to do its job, probably after scrubbing it in with a toothbrush or something small enough to get between the tiles. The bleach comes in both powder and liquid form.

We used an oxygenated-bleach product to clean the grout in the shower at our house. Though it didn't work as well as we thought chlorine bleach and water would, no one was overcome by fumes.

Some people swear by white vinegar, others by baking soda, still others by household cleaners. Whatever works best for you is fine. There are commercial tile cleaners on the market too, but they might contain chemicals you might not want to have around the house.

As with everything in the house that's used regularly, the grout in your bathroom won't stay clean, especially old grout that hasn't been maintained. You might try a commercial grout sealer after you clean, but eventually you'll have to do it again.

Q: I'm remodeling my bathroom and am planning to change the tiles in my shower. My builder tells me it's OK to put new tiles over old.

A: If the old tile is still tightly bonded to the substrate and if there are no loose, cracked or broken tiles, then yes. Glazed tile will have to be roughed up to take the adhesive.

Q: I bought a single home with an attached, windowless garage. The former owner used the garage as a smoking room. I paid a professional painter to apply a primer to the drywall to help eliminate the odor. A top coat of latex was applied over the primer.

Eight months later, the odor is still present, especially in periods of high humidity. I am seeking a way to eliminate the odor without removing the drywall.

A: Tobacco odor is the toughest thing to get rid of, and requires patience. I talked with a few painting experts and a chemist about the problem, and here's the best I could come up with:

Nicotine particles are small enough to bleed through latex paint. Your painter should have used a cleaning agent containing ammonia or glycol, which tends to neutralize the particles.

To kill the odor, the primer used should be at least two coats of Kilz; B-I-N, the Zinsser product that contains shellac and is a stain-hider, or some similar product. Then rather than latex, an oil-based paint  should be applied, two coats of it. (Supplies are limited, so you may have to look around a bit to find it.)

I'm not guaranteeing this method will do the job, but painters tell me it has the best chance of succeeding.

Follow-up: A reader who recently asked about a paint-removal process for shutters that involved placing them in a steam box stumped my paint-industry sources and me, but not my readers.

Tim Wood at the Chestnut Hill Historical Society and John Cluver identified Duffy Hoffman of Pipersville as the historic-preservation expert who demonstrated the paint-stripping process at a recent home show in King of Prussia. From my reading, the process limits exposure to lead-based paint, which makes perfect sense.

For more information, call Hoffman Painting & Refinishing Inc. at 215-766-3544. Wood forwarded a link to a Web site showing the process: http://www.historichomeworks.com/hhw/index.htm.