Q:My kids have grown up on our 27-foot cuddy cabin boat. It's the worse for wear, but we still love the old boat. Recently, I've noticed that the padded vinyl trim has become badly stained with mildew, which doesn't come off with regular cleaners. What can I do?
- Lou Deeter, Springfield, IL

A: My friend Darryl makes canvas and vinyl upholstery for a living. His suggestion is to mix an ounce or so of regular household bleach into a quart of water. Fill a spray bottle with this mixture. Wet the mildew with a mist  of bleach water and let it soak for a moment. The mildew should wipe away from the upholstery.

This seemed too simple a solution to me, so I tried it on a boat we were detailing in the shop. It works, but there are a few things to keep in mind. The solution should be fairly diluted. Apply just enough to wet the surface, but not so much that the bleach water drips off, since drips can cause spotting on some materials. Don't let the overspray contact any nearby fabrics, especially curtains and fabric upholstery. Bleach can remove some types of fabric dyes. It'll also leave white spots on your favorite blue jeans if the bottle drips.

Removing mildew is one thing, but preventing it is another. You need to find the source of the moisture that promotes mildew growth. My guess is that you have a leaking side window, a typical problem on older boats. Other possibilities include loose deck hardware and even sprung hatches. It doesn't take much water to make the interior of a boat moist enough for those dreaded black spots to appear.

There's really no easy "fix" for leaking windows. Most of the time it's not the caulk around the window frame that's the culprit; the water comes through the worn seal between the sliding glass and the track in which it moves. About the only cost-effective thing you can do is clean out any weep holes to make sure water drains out of those tracks.

Some people have canvas window covers made for their boats. These should be cut to the shape of the windows and made out of the same color material as the boat's other canvas covers. When snapped into place, these covers keep rain water from collecting in window tracks while the boat isn't in use. This same canvas cover idea can be applied to deck hatches as well.

Ventilation is the second way to prevent mildew. It seldom grows where there's good airflow. You may find that propping the toilet room door open during the week will give enough air movement to prevent the problem.

Lastly, clean all vinyl surfaces regularly. Airborne dirt and even grease from cooking all cling to padded vinyl trim. The result is an invisible coating of what amounts to mildew food. A few minutes of work each fall can prevent hours of drudgery in the spring.

Send your BoatCraft Q&A questions to Dave Brown c/o Boating World , 2100 Powers Ferry Road, Atlanta, GA 30339. You can also e-mail your questions to editor@boatingworld.com. Due to the volume of inquiries, Dave Brown will be unable to answer  every question.