How Can You Master Masonry Waterproofing Techniques?

A Comprehensive Guide to Masonry Waterproofing

Ever wondered how ancient stone structures manage to withstand centuries of exposure to the elements? The answer lies in a precise technique known as masonry waterproofing. This essential step in construction helps to defend our beloved buildings, whether brick, stone, or concrete, against the harmful effects of water. But what does masonry waterproofing entail, and why is it so important?

In this guide, we will thoroughly explore the world of masonry waterproofing. We’ll explore its basics, understand why it’s vital, and look at different methods employed to protect our structures. We’ll take a detailed glance at each waterproofing technique, from surface sealers to penetrating sealers, and even waterproofing membranes. Plus, we’ll provide a step-by-step application process.

To top it all off, we’ll look at some highly recommended waterproofing products and explore additional waterproofing techniques like additives, damp proof courses, and drainage systems. Ready to get started? Let’s begin!

Understanding Masonry Waterproofing in Construction

Masonry Waterproofing Basics

Masonry waterproofing is the process of applying materials and techniques to protect masonry structures, like brick, stone, and concrete, from water damage. This ensures the longevity and durability of the structure by preventing water penetration and subsequent deterioration.

Why Masonry Waterproofing is Important

• Prevents Water Damage: Water can erode masonry materials, leading to structural damage.
• Avoids Mold Growth: Damp environments can promote mold growth, posing health risks.
• Enhances Durability: Proper waterproofing extends the life of masonry structures.
• Minimizes Maintenance: Reducing water infiltration decreases the need for repairs.

Methods of Masonry Waterproofing

There are several methods used to waterproof masonry. The choice depends on the structure’s requirements and the extent of exposure to water.

Surface Sealers

Surface sealers are coatings applied to the exterior of masonry surfaces. These sealers form a protective, water-resistant barrier.

• Types: Acrylics, silanes, siloxanes
• Benefits: Easy to apply, cost-effective, enhances appearance

Penetrating Sealers

Penetrating sealers work by soaking into the masonry material and creating a hydrophobic (water-repelling) layer within the substrate.

• Types: Siliconates, silicates
• Benefits: Long-lasting, doesn’t alter the appearance, effective against moisture

Waterproofing Membranes

Waterproofing membranes are sheet materials or liquid-applied coatings that form a continuous barrier against water. They are often used in areas subjected to heavy moisture.

• Types: Liquid rubber, bituminous membranes
• Benefits: High durability, excellent protection, suitable for large surfaces

Application Process

Step	Description
1. Surface Preparation	Clean the masonry surface to remove dirt, dust, and debris.
2. Repair Damages	Fix any cracks, holes, or damaged areas to ensure a smooth surface.
3. Apply Waterproofing Material	Use the chosen waterproofing method (sealer, penetrating solution, or membrane) evenly across the masonry.
4. Allow Curing	Give the waterproofing material adequate time to set and cure as per manufacturer’s instructions.

Common Waterproofing Products

Some widely recommended waterproofing products include:

• Thompson’s WaterSeal Clear Multi-Surface Waterproofer
• Drylok Extreme Masonry Waterproofer
• SEAL-KRETE Clear-Seal Low-Gloss Sealer

Exploring Additional Waterproofing Techniques

Exploring Waterproofing Additives

While sealers and membranes are common waterproofing methods, additives provide another option. These substances are mixed directly into concrete, plaster, or mortar during the construction process. As a result, they imbue the entire structure with water-resistant properties instead of just the surface. Additives can be divided mainly into two categories: integral water repellents (IWRs) and crystalline waterproofing additives.

Integral Water Repellents (IWRs)

IWRs are additives mixed into the concrete during the manufacturing process to make the material inherently water-resistant. They work by reducing the concrete’s wettability, making it hydrophobic.

• Types: Fatty acid derivatives, Stearates, and Petroleum-based products
• Benefits: Widespread efficacy, durable, reduces permeability, improves freeze/thaw durability of masonry

Crystalline Waterproofing Additives

Unlike IWRs, crystalline waterproofing additives chemically react with water and un-hydrated cement particles to form insoluble, needle-like crystals. These crystals block the capillaries and shrinkage cracks in the concrete to prevent any water ingress.

• Types: Xypex, Kryton Krystol Internal Membrane(KIM)
• Benefits: Permanently waterproofs the structure, self-seals cracks, improves durability of structure

Implementing Damp Proof Course (DPC)

Damp Proof Course is an approach used to combat rising damp—a phenomenon where water from the ground rises up through the structure via capillary action. This technique involves inserting a horizontal barrier of impervious material into the wall above ground level.

• Types: Bitumen, mastic asphalt, plastic, slate, lead, copper, etc.
• Application: Laid at least 6 inches above ground level and below all wet areas in the structure, like bathrooms and kitchens
• Benefits: Prevents structural damage, improves the durability of the structure, reduces mold and mildew growth

Considering Drainage Systems

Proper drainage systems are an essential part of waterproofing strategies. They help direct water away from the structure, preventing accumulation and infiltration. From French drains to sump pumps, a variety of systems can be implemented depending on the specific needs of the building and its surroundings.

French Drains

Often used in basements and other sub-surface structures, French drains are trenches filled with gravel containing a perforated pipe that redirects surface water and groundwater away from the structure’s foundation.

• Benefits: Redirects water, easy to install, blends into the landscape

Sump Pumps

Used predominantly in basements that sit below the water table, sump pumps remove water that accumulates in a sump basin and safely directs it away from the house.

• Benefits: Effectively manages water accumulation, provides additional protection against flooding

Using Waterproofing Paint

Waterproofing paint—an alternative to sealers and membranes—can be especially useful for interior walls. As the name suggests, this paint provides a waterproof coating to the wall’s surface.

• Types: Acrylic, latex-based, oil-based, and elastomeric
• Application: Rolled or brushed onto clean, dry walls
• Benefits: Provides a decorative and waterproof finish, effective barrier against minor dampness, ideal for interior walls

As per a guide from Bob Vila, some top waterproofing paint brands include KILZ, AMES, and Drylok. Remember, consistency and thoroughness are essential for all these waterproofing methods to give your masonry the most robust defense against water damage.

How to Apply Masonry Waterproofing

Masonry Waterproofing Process

Applying masonry waterproofing requires careful planning and execution to ensure the treatment is effective. Here’s a practical guide to follow:

Step 1: Surface Preparation

Preparing the surface is an essential first step before applying any waterproofing materials.

• Cleaning: Remove dirt, dust, mortar splashes, grease, algae, and other contaminants using a wire brush, pressure washer, or chemical cleaner as appropriate.
• Dampening: Lightly dampen the masonry surface. This helps in the even absorption of the waterproofing material.

Step 2: Repair Damages

Before you can waterproof masonry, any structural defects need addressing.

• Identify Issues: Look for cracks, gaps, holes, or any deterioration.
• Fill Cracks: Use masonry repair mortar or a suitable filler to patch up cracks and holes. Ensure the filler is compatible with the type of masonry.
• Levelling: Surface should be smooth and level for the waterproofing material to adhere properly.

Step 3: Choose and Apply Waterproofing Material

Selecting the right waterproofing material is essential depending on the specific needs of the masonry structure.

Surface Sealers Application

• Mixing: Shake or stir the sealer thoroughly according to the manufacturer’s instructions.
• Application: Use a brush, roller, or sprayer to apply the sealer evenly. A thin, even coat is better than a thick, heavy one.
• Drying Time: Allow sufficient drying time before applying a second coat if necessary.

Penetrating Sealers Application

• Mixing: Some products might require mixing or activation, check the label.
• Application: Apply with a low-pressure sprayer or roller. Ensure the surface is saturated but not excessively flooded.
• Drying Time: These sealers typically do not leave a surface film. Allow drying as indicated on the product.

Waterproofing Membranes

• Primer: Apply a primer if required by the membrane product to ensure good adhesion.
• Application: For liquid membranes, use a brush or roller to apply. For sheet membranes, carefully lay and adhere to the surface without air bubbles or wrinkles.
• Overlaps: When using sheet membranes, follow specific instructions for overlaps and seals to ensure no gaps.

Step 4: Allow Curing

The curing process is vital for the longevity of the waterproofing treatment.

• Time: Follow the curing time recommended by the manufacturer. This can range from several hours to a few days.
• Conditions: Ensure the treated area remains dry during the curing period, especially for membrane applications.

Additional Tips

Consider these additional tips to maximize the effectiveness of the waterproofing process:

• Weather Conditions: Choose a time for application when the weather is mild and dry to ensure optimum adhesion and curing.
• Sufficient Coverage: Apply enough product to saturate the surface but avoid pooling or excessive layering.
• Regular Maintenance: Inspect the masonry regularly and reapply waterproofing treatments as necessary to maintain protection.

Proper application of masonry waterproofing will protect the structure from moisture-related damage and extend its longevity. Refer to expert guides and manufacturers’ instructions for specific details. Family Handyman offers detailed tips and advice on effective waterproofing techniques.

In Conclusion

We’ve explored several waterproofing methods for masonry, ranging from surface and penetrating sealers, waterproofing membranes, to additives, Damp Proof Course, and effective drainage systems. The choice depends on your structure, location, and specific waterproofing needs.


Fundamentally, good masonry waterproofing not only extends the lifespan of your structure but also prevents potential health hazards like mold growth. It could be as simple as applying a good sealer or as comprehensive as installing an effective drainage system to handle extreme conditions. Note that consistency and adherence to a procedural application process are critical for the functional longevity of the waterproofing treatment.

Frequently Asked Questions – FAQs