QWe recently bought an older house and many of the floors were finished with stone tiles -- quarry tiles or terrazzo, I suppose. They were dirty and I cleaned them with a scrub brush and detergent. What do I do now to keep them that way? Should I wax them? The grout is also coming loose in places. -- B. Shea

AA number of sealers are available for quarry tiles, terrazzo, slate and various types of unglazed tiles. A couple of brand names are 3M Cornerstone and CeramaSeal. You should be able to find an appropriate sealer at a home center or tile dealership. Applying a sealer will enhance the appearance of the tiles as well as provide protection against dirt and stains. Many sealers will also help protect the grout.

Before applying a sealer, you should remove and replace loose grout. Grout products are also available at home centers and tile dealerships, although you might have trouble matching the exact color of the old grout.

Avoid using wax, which could make the tiles very slippery.

Our clothes dryer is in the basement. Because of the construction of the house, there is no short, direct way to vent the dryer to the outdoors. A repairman told us to vent it into the crawl space under a room addition. What do you think? -- K. Goeller

Dryers should not be vented into crawl spaces, attics or similar spaces. The lint, which can cause fires if allowed to accumulate, and moisture expelled by the dryer can create serious problems.

However, electric clothes dryers can sometimes be vented indoors if they are equipped with a special vent kit and the lint is cleaned out frequently. This is not an ideal solution and might not be permitted in some areas. If you decide to try it, check with your local building inspector to see if it is allowed. Indoor vent kits for electric dryers are available at some home centers and hardware stores.

Gas clothes dryers should never be vented anywhere but to the outside. There is usually a reasonable way to do this, no matter how the house is constructed. If necessary, move the dryer to another location to make proper venting possible.

I live in an apartment with central air conditioning and heating. We are having problems with odors. The indoor humidity level is 69 percent. Any suggestions? -- R. Bailey

It may or may not be the cause of the odors, but your humidity level is far too high. An indoor relative humidity of less than 50 percent is recommended. Excessive humidity can cause mold to form, which can result in a musty odor and can cause or aggravate respiratory ailments. Here are some steps to take:

* Determine whether the excessive moisture might be caused by the heating-cooling system. If there is a humidifier, it should be turned off or set back.

* Expel excess moisture from your home by using exhaust fans in the bathroom, kitchen and laundry. Make sure your clothes dryer is vented to the outside.

* Keep a close check on the humidity level. If you do not have a hygrometer, buy one.

* Use dehumidifiers, if necessary to reduce the moisture level.

* Keep a close watch for mold formation. For more information on how to deal with mold, go to www.epa.gov and click on "Mold" in the index at the top of the page.

Questions and comments may be sent to Gene Austin, 1730 Blue Bell Pike, Blue Bell, Pa. 19422. Send e-mail to doit861@aol.com.