Should I waterproof or seal my masonry

Key Considerations:

1. Seal (Water Repellent): Best for above-grade brick, stone, and concrete. These penetrate the surface, allowing vapor to pass through (breathe) while repelling liquid water.

2. Waterproof (Film-Forming): Suitable for interior basement walls, not exterior surfaces, as they can trap moisture and fail, causing damage.

Benefits: Reduces efflorescence, protects against moss/mildew, and extends the lifespan of masonry.

When to Act:

If your bricks feel damp for long periods, have white powdery salt (efflorescence), or have cracking mortar joints, it is time to seal.

Best Practices:

1. Clean first: Remove all dirt and mildew before applying any product.

2. Test breathability: Ensure the sealer is breathable, especially for older, softer bricks.

3. Apply to dry masonry: Water trapped inside before sealing will cause damage

Hydrophobic masonry sealers are penetrating treatments that chemically bond within the pores of brick, stone, and concrete to create an invisible, water-repellent barrier. Unlike film-forming coatings, these "breathable" sealers allow moisture vapor to escape while causing liquid water to bead and roll off the surface. 

Elastomeric masonry sealers are flexible, rubberized coatings designed to protect porous surfaces like concrete, stucco, and brick by bridging cracks and preventing water intrusion. Unlike standard sealants, these products can expand and contract, allowing them to move with a structure as temperatures fluctuate without cracking or peeling. Nonslip applications can be added to for better traction on high traffic pedestrian areas

Elastomeric and hydrophobic sealers are both designed to protect surfaces from water, but they function in fundamentally different ways: elastomeric sealers focus on flexibility and bridge gaps (membrane forming), while hydrophobic sealers focus on repelling water (surface penetration).

Here is the breakdown of the differences:

1. Mechanism of Action

Elastomeric Sealer: Creates a thick, rubbery, and flexible membrane on top of the surface. It is designed to stretch and return to its original shape, which allows it to span or "bridge" hairline cracks in materials like concrete and stucco, preventing them from leaking.

Hydrophobic Sealer: Repels water on a molecular level. It penetrates into the pores of the substrate (like concrete or brick) and lines them to repel water, rather than creating a visible layer on top.

2. Flexibility and Movement

Elastomeric: Highly flexible (high elongation properties). It is designed for structures that experience thermal expansion and contraction (e.g., roof systems or cracking concrete).

Hydrophobic: Not inherently flexible. It is designed to change the surface tension of the substrate to make it water-repellent (causes water to "bead").

3. Application and Appearance

Elastomeric: Usually applied in thick coats (like thick paint) and typically dries to an opaque, sometimes white or colored finish.

Hydrophobic: Often clear and invisible. It does not change the look or texture of the substrate, making it ideal for brick, stone, or architectural concrete.

4. Permeability ("Breathing")

Elastomeric: Generally, these are less breathable or impermeable, creating a total barrier, although some formulations allow low moisture vapor transmission.

Hydrophobic: Usually highly breathable, allowing water vapor to escape from inside the material while preventing liquid water from entering. waterproof seal masonry