All surfaces should be cleaned before sealing, staining or painting for the best penetration and performance of a coating. Even new wood can have dirt or other invisible barriers to coating penetration. For instance, new wood can have an invisible mill glaze caused when the heat of the milling equipment reacts with natural oils in the wood.

Here is a basic guide to follow when selecting a wood cleaning product.

For Wood and/or Composite Surfaces

If You Need To Remove:	Use:
Stains from dirt, mildew, algae & fungus and there is little or no trace of a residual finish.	Thompson's® WaterSeal® Deck Wash
Weathered clear & tinted waterproofers or semi-transparent stains in addition to stains from dirt, mildew, algae & fungus.	Thompson's® WaterSeal® Heavy Duty Deck Cleaner
Oil & water based solid stains and long-lasting, hard-to-remove semi-transparent stains & waterproofers in addition to stains from dirt, mildew, algae & fungus.	Thompson's® WaterSeal® Maximum Strength Deck Stripper
On REDWOOD/ CEDAR/ HIGH EXTRACTIVE Wood: Tannin staining and restore lighter color of redwood/ cedar/ mahogany or other high extractive wood species in addition to remove stains from dirt, mildew, algae & fungus and/or, as instructed, to neutralize any wood species after using other cleaners.	Thompson's® WaterSeal® Deck Cleaner & Brightener

For Exterior Multi-Surfaces

If You Need To Remove:	Use:
On EXTERIOR SURFACES such as Wood & Composite Decks, Fences, Concrete & Masonry, Outdoor Furniture, Roofs & Siding: Stains from dirt, mildew, algae and fungus with a non-bleach, chlorine-free oxygenated foaming formula.	Thompson's® WaterSeal® Oxy Foaming Action Exterior Multi-Surface Cleaner