Ponding water is one of the most destructive conditions for flat and low-slope roofs. When water sits on a roof for extended periods, it accelerates coating breakdown, causes leaks, and shortens the life of the entire roofing system. Choosing the right roof coating for ponding water is critical—and this is where Gaco 100% silicone roof coatings stand out.

In this article, we’ll explain what ponding water is, why many coatings fail, and why silicone specially Gaco wins in these conditions.

What Is Ponding Water on a Flat Roof?

Ponding water occurs when water remains on a roof surface longer than 48 hours after rainfall. This is common on flat roofs with:

• Inadequate slope

• Blocked or insufficient drains

• Settled or deflected roof decks

Over time, standing water attacks roof materials and exposes weaknesses in coatings that are not designed to handle constant moisture.

Why Most Roof Coatings Fail Under Ponding Water

Many traditional roof coatings perform well in dry conditions but break down when submerged.

Common failures include:

• Softening or re-emulsification

• Blistering and bubbling

• Loss of adhesion

• Premature cracking and peeling

Acrylic, asphalt-based, and some elastomeric coatings are especially vulnerable to long-term water exposure.

Why Silicone Is the Best Roof Coating for Ponding Water

100% Silicone Is Unaffected by Standing Water

Unlike other coating chemistries, 100% silicone does not soften, break down, or lose adhesion when submerged. This makes it the top choice for roofs where ponding water cannot be fully eliminated.

Why Gaco Silicone Outperforms Other Silicone Coatings

Gaco has built its reputation around high-performance silicone technology designed specifically for real-world roofing challenges.

Key Advantages of Gaco Silicone Roof Coatings

Exceptional Ponding Water Resistance

Gaco silicone coatings remain stable under continuous standing water, maintaining their waterproof barrier year after year.

Seamless Waterproof Membrane

Once cured, Gaco silicone forms a fully adhered, seamless membrane that seals cracks, seams, fasteners, and penetrations.

Superior UV Resistance

Gaco silicone resists UV degradation, reducing cracking and surface wear caused by prolonged sun exposure.

Long-Term Durability

Silicone does not chalk or degrade like acrylics, resulting in fewer repairs and longer service life.

Wide Substrate Compatibility

Gaco silicone adheres to common roof surfaces such as:

• Modified bitumen

• Built-up roofing (BUR)

• Metal

• Spray polyurethane foam

• Concrete

• Single-ply systems (with proper prep)

Gaco Silicone vs Other Roof Coatings for Ponding Water

Coating Type	Ponding Water Resistance	Long-Term Performance
Acrylic	Poor	Breaks down when wet
Asphalt	Poor	Softens and cracks
Polyurethane	Fair	Can degrade over time
100% Silicone (Gaco)	Excellent	Unaffected by standing water

When Gaco Silicone Is the Right Choice

Gaco silicone roof coatings are ideal when:

• Ponding water cannot be fully corrected

• A roof restoration is preferred over replacement

• Long-term waterproofing is required

• Minimal maintenance is a priority

For commercial, industrial, and residential flat roofs, silicone offers peace of mind where other coatings fail.

Conclusion

If your roof experiences standing water, not all roof coatings are created equal. Silicone is proven to outperform other coating types under ponding water conditions—and Gaco silicone leads the category with long-lasting waterproof protection, UV resistance, and durability.

When ponding water is unavoidable, Gaco silicone isn’t just a good option—it’s the best option.