Water popping hardwood flooring is a step between the sanding and the stain being applied. Water popping is when an even layer of water is applied to the hardwood. The water can be applied in a variety of ways including wiping it onto the floor with a towel, mopping it on or using a mister. None of these methods is better or worse than the other, it all comes down to personal preference. The water needs to be applied evenly to ensure a consistent stain. You may here a hardwood professional talking about grain popping, popping the grain or other similar phrases, these all refer to water popping.
The waterpopping process reopens the grains after the sanding process. Wood is still able to retain and expel moisture after the kiln drying process. The wood will react to the moisture levels in its environment so when the water layer is added to the top it will cause the pores to swell. This process allows the stain to penetrate the wood deeper through the natural pores. A water popped floor will likely have a richer and deeper color stain and this process works especially well with dark stain choices.
Water popping is not something that is done on every floor. The color of stain you choose will affect the choice to water pop the floor. Light or natural stain colors are not water popped. Some wood species are not water popped because it can cause the stain to look more blotchy, maple is an example of this.
Exotic hardwoods are generally rich in color and grain naturally and rarely stained. Most exotic hardwoods have a high oil content and should not be waterpopped. Some exotics even need to be wiped down with alcohol before finishing to remove oil that could affect adhesion.
Mineral spirits or paint thinner should not be used as a water popping agent. These liquids will leave a residue on your floor that can cause discoloration and can affect adhesion. These products are harsh and can really damage your wood.
Water popping can add a rich luscious color to your stain. The extra step doesn’t add much time to the project but makes a big impact.