Dale in Oklahoma asks, “What is the difference between water washing and brushing a pebble finish to expose the aggregates?”
Jon Temple of Tempool Inc., fields this edition’s question. He’s used both techniques over the years, (and recognizes there’s pros and cons to each) but says “You’re in good hands with an applicator who uses either technique as long as they’re CLI Authorized.”
The two most common processes for exposing pebble finishes are to use water wands or nylon brushes to remove the “cream.” The “cream” is a mixture of dye and cement that is forced to the surface during the troweling process. The cream must be removed in order to expose the pebbles. When using water wands, the applicators use a maze of low pressure spray hoses to wash away the cream during the troweling process. The applicators go back and forth between spraying and troweling.
On the other hand, the brush exposure technique happens after the plaster has been troweled and hardens. Applicators will use a common garden hose to spray the surface then use a series of brushes to remove the cream. After the aggregate is exposed and the finish cures for 24 hours, the application team will return to acid and pressure wash the surface. This happens for both water wand and brush exposures.
Water Wanding Exposure Pros:
- Slightly more resistant to water chemistry abuse, because there is less cementitious material exposed.
- Nearly identical to the product samples.
- Faster overall process.
- Extremely even exposure.
Brush Exposure Pros:
- Reduced cleanup time.
- Smoother finish.
- More water color variety, because there is more colored cementitious material exposed.
- Less job site waste.