A reader wants to know how to clean this dingy grout. (Reader photo)

Q: My bathroom has tiles as small as one inch square in a repeating pattern common in bathrooms from the 1960s. Over the years, the grout has become quite dark, especially away from the corners, which I think indicates it is primarily dirt. I have tried many cleaning products, such as scouring powder and bleach, but have had no success. Do you have any suggestions?

Columbia, Md.

A: The Tile Council of North America, a trade association that represents manufacturers of tile and related products, recommends cleaning grout with an alkaline cleaner, such as Spic ’n Span or Mr. Clean. The association warns against acid-based cleaners, which can eat into grout, and cleaners with oil or wax, such as Murphy Oil Soap and Pine-Sol, because they can leave a sticky residue on grout. If the alkaline cleaners don’t work, the association recommends trying an enzyme cleaner labeled for use on tile. An example is Rejuvenate RJ24BC Bio-Enzymatic Tile & Grout Everyday Cleaner ($5.97 for a 24-ounce spray bottle at Home Depot).

However, the best tip from the council probably isn’t what cleaner to use; it’s the process. Because grout is porous, grime picked up by the cleaning solution often tends to re-lodge within the grout pores. To overcome this, the council recommends using a shop vacuum to whisk up the cleaning solution. Apply clean water and vacuum that up, too, so you rinse the floor thoroughly. Or, even better, the council says, use a steam cleaner. One machine that’s suitable for small spaces such as a bathroom is the McCulloch MC1275 Heavy-Duty Steam Cleaner ($139.13 on Amazon).

Another option is to hire a company that specializes in grout cleaning and repair. Potomac Stone Care in Sterling, Va. (703-444-4901 in Virginia or 301-765-3451 in Maryland and the District; potomacstonecare.com), cleans grout using the same vacuum-extraction process that the tile council recommends, with the addition of a mechanical scrubber to help dislodge dirt. If the grout doesn’t come clean, the company can coat the grout with a colorant at a higher price. And for even more money, it can grind out the grout and redo it with whatever color you want. The company has a minimum fee of $400, and the cost for a complete grout redo often runs around $600 for a standard bathroom, said Steve Kivinski, the president. However, the cost could be higher for a floor with tiny tiles because there is so much grout in proportion to the overall area, and dealing with the grout takes the most time.

A reader wants to refinish this 30-year-old teak laminate table, which is dry and water-stained. (Reader photo)

Whatever approach you take, once you get the grout looking as good as it can, be sure to apply a quality sealer to make it easier to clean in the future.

We have a 30-year-old teak laminate table from Scan that I’d like to refinish. The surface is dry, water-stained and generally neglected. Because it is laminate and not solid teak, I worry about damaging the top layer. Can I take fine-gauge steel wool to it and then re-oil it?

Arlington

Scrubbing with fine-gauge steel wool and then applying oil is often appropriate as a way to restore the surface on teak furniture, whether it’s solid teak or laminated with just a teak veneer. Brandon Webster of Gallery 2112, a D.C. dealer of mid-century modern furniture, sculpture and art, said that’s often what he does. However, after looking at the pictures you sent, he suggested the damage might be too much for this simple approach to work. Also, given the vintage of your table, he said he fears the original finish was not oil but lacquer or even polyurethane, which wouldn’t respond well to the treatment you suggest.

He recommended turning to Jeremy Fair, who ran Modern Laboratory Restoration, a furniture-repair company in Washington, until it closed after a fire a year ago.

Fair, who can be reached at 703-347-5088 or modlabdc@gmail.com, looked at the pictures and said he is virtually certain the original finish was lacquer. He said he would carefully sand off the finish, treat any remaining dark stains with oxalic acid, oil the surface to bring out the grain, then spray shellac sealer followed by two or three coats of lacquer. He estimated the cost at $950 to $1,250.

Or you could follow a similar approach and do the work yourself. Katie Schoenbauer Morgan of the furniture-restoration company Schoenbauer Furniture Service (800-955-7603; schoenbauer.com) said her company advises DIYers who want to restore tables like yours to sand the surface, using nothing coarser than 220 grit. (You can sand by hand, going in the direction of the grain, or if you are very careful and used to using a power sander, do the initial work with a random-orbit sander, followed by hand-sanding.) Wipe away all the dust. An oil finish is the easiest final step. Build it up in layers over several days. Or, if you have access to spray equipment, you can spray on lacquer, which is more resistant to damage from oil and water.

Doug Meyers, owner of Modern Mobler (202-882-1648; modernmobler.com), a store in the District that carries a lot of Scandinavian modern furniture, recommends the same basic approach as Morgan: sanding with 220-grit sandpaper, then oiling. “You’re going to want to apply multiple coats of teak oil to build up the finish again,” he said.

Have a problem in your home? Send questions to localliving@washpost.com . Put “How To” in the subject line, tell us where you live and try to include a photo.