Wood and water definitely don't mix. This should be kept in mind when you decide it's time to clean your hardwood floor again. Prefinished hardwood floors and hardwood floors that are finished in place are not the same. Prefinished hardwood ones should be cleaned and waxed with products available from their makers. You must do this to preserve the warranty and the life of the floor. This is because their cleaners are completely compatible with their own factory finish. Use a 5-percent vinegar-and-water solution on custom hardwood floors. One last time: water and wood don't mix. Mop one extra time before you put it on the floor. How often should you clean? My wife has me do it once a week. And that's the On The House tip for today.