Waterproofing is essential for protecting your home from water damage, mould, and long-term structural issues. The primary goal of waterproofing is to prevent water from entering. This guide will outline the most effective ways to waterproof external walls and avoid costly repairs later.
Let’s get straight to the point.
Waterproofing your external walls is important to protect your home from water damage, mould, and structural issues. The process involves inspecting and repairing cracks, using appropriate waterproofing materials, and ensuring proper ventilation to prevent moisture buildup.
Start by preparing the walls through repairs, cleaning gutters, and choosing breathable waterproofing products like concrete- and silicate-based coatings. Add plaster waterproofing additives for extra protection, especially in areas prone to cracks.
Perform a water-tightness test after applying waterproofing products. Address common water entry points like roof-wall junctions and concrete gutters, ensure proper drainage systems, and handle rising dampness with polymer paint.
Preparing External Walls For Waterproofing
Repairing Cracks And Holes
It is vital to repair all cracks and holes before applying waterproofing materials. Allow a high-quality filler to dry fully before sanding or grinding the surface to create a smooth, dust-free finish. This ensures the waterproofing solution adheres effectively.
Tools For Application
Apply waterproofing products using a high-quality roller or brush. If a second coat is needed, allow the first coat to dry completely before proceeding. Ensure the waterproofing layer is solid and thick enough to prevent water penetration.
Waterproofing External Walls: Step-By-Step
Step 1: Inspect The Wall For Damage
Before starting any waterproofing process, inspect your walls for signs of damage, such as cracks, leaks, or structural weaknesses. Fix these issues before applying waterproofing products.
Step 2: Clean The Gutters
Clogged gutters can cause water to overflow and damage the walls. To prevent water buildup, ensure gutters are clear and properly maintained.
Step 3: Select The Right Waterproofing Product
Choose a waterproofing product designed for masonry, concrete, or painted surfaces, depending on your wall type. Plaster waterproofing additives are also helpful for reinforcing wall protection.
Step 4: Prepare The Walls For Waterproofing
Once repairs are made, smooth the wall surface by sanding and cleaning off any dust or debris. Make sure the wall is dry before applying any waterproofing products.
Step 5: Apply The Waterproofing Solution
Using a roller or brush, apply the waterproofing product evenly. If a second coat is required, wait until the first coat is completely dry. Cover the entire surface adequately to create a strong waterproof barrier.
Step 6: Test The Waterproofing
After the product has been applied and dried, perform a water-tightness test. Spray water on the wall for a few hours, then check with a moisture meter if moisture levels remain low. This ensures that the waterproofing is effective.
Special Considerations For Basements And Foundations
External Waterproofing For Basements
Water can enter a home through the basement or crawlspace. External waterproofing is necessary to protect your foundation from water damage. The process involves excavating around the foundation, cleaning the walls, and applying a polymer coating.
Installing Drainage Systems
Installing proper drainage systems is essential to prevent water buildup around your foundation. This includes drainpipes with the correct slope for continuous drainage and placing rock backfill around the foundation to filter water and prevent soil clogging.
Finding And Fixing Water Entry Points
Water infiltration can severely damage a building’s structure, so it’s important to identify and address potential entry points. Here’s a guide to inspecting and fixing common areas where water can enter:
- Inspecting the Roof and Wall Junction
Water naturally flows downward, so start by inspecting the highest points of your building. If your roof lacks an overhang, check for cracks at the top of the wall where water might be seeping in. Ensure the roof and parapet walls are properly sealed to prevent water entry.
- Addressing Leaking Concrete Gutters
Concrete gutters can develop cracks, allowing water to infiltrate walls. The cracks are repaired to fix this, and the entire gutter system is waterproofed. Ensure the downspout is wide enough to handle roof runoff and install overflow notches to guide excess water away from the structure.
- Inspecting the Wall Surface
Examine the entire wall surface for cracks or weather-related wear. In areas with strong winds, rain may hit the wall at an angle, increasing the risk of water penetration. Roof overhangs help redirect water away from the walls, reducing this risk.
- Ventilation for Moisture Evaporation
If walls become saturated with moisture, proper ventilation is essential for drying them out. Avoid sealing internal walls the same way as external ones, as this can trap moisture inside and lead to further issues. Instead, allow the walls to breathe, especially in humid environments.
- Dealing with Rising Damp
Rising dampness is a frequent issue, especially in areas without damp-proof courses. To address this, a horizontal cut is made at the base of the wall and sealed with high-density cement, a method known as “sloof.” This technique blocks water from rising into the foundation. While popular in some regions, silicone injection solutions may work better in areas with porous building materials.
- Sealing Cracks with Polymer Paint
Polymer paint offers a durable solution for treating cracks. Apply a thick coat of the paint over the crack, and for best results, use a membrane that acts like a bandage. Apply the paint, place the membrane along the crack, and saturate it with more paint. This expands the membrane while maintaining its waterproof properties, even if the crack widens over time.
By inspecting and addressing these common areas, you can effectively prevent water from entering your building and causing costly damage.
Selecting The Right Waterproofing Solution
Choosing the appropriate waterproofing solution is essential for protecting your home from moisture damage. When selecting a product, it’s important to ensure it allows the walls to “breathe.” This is important for preventing moisture buildup within the structure. Here are key considerations:
- Opt for Breathable Products:
- Select waterproofers that let moisture escape without allowing water to penetrate.
- This ensures that walls do not retain moisture, reducing the risk of mould or long-term damage.
- Concrete-Based Coatings:
- Concrete-based waterproofers are ideal for masonry surfaces.
- They form a solid, durable layer that protects against water infiltration, making them highly suitable for areas prone to heavy rainfall or constant moisture exposure.
- Silicate-Based Waterproofers:
- Silicate-based products are considered the industry standard for external wall sealing.
- These solutions are especially effective when used on materials that match concrete masonry, ensuring a seamless, long-lasting barrier.
- They can also be applied to bare or unpainted walls, providing versatile protection for various surfaces.
Using Plaster Additives
Most external plasters come with built-in waterproofing properties, but enhancing these with a waterproofing additive is a smart way to provide extra protection. Key benefits include:
- Additional Layer of Protection: Adding a waterproofing additive ensures that even small cracks or weak points in the plaster are sealed off from water infiltration.
- Prevent Water Damage: This extra layer is the key to preventing water-related issues, especially in areas where cracks are more likely to form due to ground movement or structural shifts.
Choosing the right waterproofing solution and reinforcing plaster with additives can significantly reduce the risk of water damage to your external walls.
Conclusion
Waterproofing your external walls is essential in protecting your home from costly water damage, mould growth, and long-term structural issues. By following the right processes—repairing cracks, selecting appropriate waterproofing products, and ensuring proper drainage—you can prevent water infiltration and maintain the integrity of your walls.
Additionally, using plaster additives and regularly inspecting vulnerable areas like roof-wall junctions and gutters will further safeguard your home. Taking these preventive measures will not only enhance the durability of your home but also improve its overall value and longevity. Proper waterproofing is a long-term investment that ensures a safe, dry, and comfortable living environment.
FAQs About Exterior Wall
How Do You Waterproof A Wall From The Outside?
Waterproofing a wall from the outside is relatively straightforward and can be finished in a few straightforward steps.
- You must apply a waterproofing sealant to the wall to continue functioning properly.
- You must apply a membrane that acts as a waterproofing agent to the wall.
- After applying the membrane, you must wait at least twenty-four hours before it dries before conducting any test.
- Following these steps will help you waterproof your wall from the outside, keeping the inside of your home dry and comfortable.
Do You Need To Waterproof The Exterior Walls?
If your home’s exterior walls are not waterproofed, you can face damage from invading moisture. Damp walls are excellent breeding grounds for mildew and mould, which can damage the home and lead to health problems for occupants. However, such damage can be avoided with proper waterproofing of a home’s exterior walls.
Is Waterproofing Brickwork A Good Idea?
The added benefit is that it still allows your walls to ‘breathe’. Without breathability, the dampness in your walls can’t evaporate, allowing your wall to dry out. Water-repellent creams dry clear, allowing any exposed brick to keep its original appearance.
Should You Seal The Exterior Brick?
The brick is extremely porous to absorb water like a sponge; over time, this water absorption can cause crumbling and cracking in the brick. Apply a sealer to your exterior brick to protect against water damage and minimise moss growth.
Can You Seal Old Brick Walls?
Clean the wall with a mild masonry stain remover or detergent solution if masonry staining is an issue. Rinse, then allow the brick and mortar to dry thoroughly before applying the sealer. Polyurethane or acrylic sealers are among the longest-lasting brick sealers, and they can give the brick a slight sheen.
