Yes, you can add water to elastomeric paint for thinning purposes, but only if necessary and within a specific limit.
Based on typical guidelines provided by manufacturers, such as the information stating "thin with not more than 125mL water per gallon paint", adding a small amount of water is permissible under certain conditions.
Why Thin Elastomeric Paint?
Elastomeric paint is known for its thick, durable coating designed to bridge hairline cracks and provide a flexible, waterproof barrier. However, its thickness can sometimes make application challenging, particularly in certain temperatures or with specific application methods (like spraying, though thinning for spraying might have different requirements not covered by the reference). Thinning with water is typically done to improve flow and workability.
The Specific Limit for Thinning
It is crucial to adhere strictly to the manufacturer's recommendations when thinning any paint, especially a specialized coating like elastomeric paint. Adding too much water can compromise the paint's key properties, such as:
- Film build: The thickness needed for crack bridging and waterproofing.
- Adhesion: How well the paint sticks to the surface.
- Durability: The lifespan and protective qualities of the coating.
- Elastomeric properties: The paint's ability to expand and contract.
According to the provided reference:
- General Recommendation: Use the paint "as supplied".
- If Necessary: You can thin it.
- Maximum Water Limit: Do not add more than 125mL water per gallon paint.
This precise limit ensures that while flow is improved, the essential performance characteristics of the elastomeric paint are not significantly degraded.
Thinning Guide
| Paint Volume | Maximum Water Allowed |
|---|---|
| 1 Gallon | 125 mL |
| 5 Gallons | 625 mL |
Note: Always measure carefully to avoid exceeding the maximum limit.
Best Practices
- Only Thin When Necessary: Avoid thinning if the paint applies well directly from the can.
- Measure Accurately: Use a measuring cup to ensure you do not exceed the recommended 125mL per gallon.
- Mix Thoroughly: After adding water, stir the paint well to ensure the water is evenly incorporated.
- Test Small Amount: If unsure, thin a small amount of paint first and test its application.
Adding water beyond the manufacturer's specified limit is not recommended and could lead to poor performance and premature coating failure.
