How to Fix a Leaky Balcony After Waterproofing Failure


A leaky balcony can be a homeowner’s nightmare. It not only ruins the aesthetics of your outdoor space but also poses a threat to the structural integrity of your home. One common cause of a leaky balcony is waterproofing failure. If you’re facing this issue, don’t worry – we’ve got you covered. In this comprehensive guide, we’ll show you how to fix a leaky balcony after waterproofing has failed, step by step.

Identifying the Problem

Before you start fixing your leaky balcony, it’s crucial to identify the extent of the damage and pinpoint the areas where the waterproofing has failed. Here’s how you can do it:

1. Visual Inspection

Begin by visually inspecting your balcony for signs of damage. Look for cracks, peeling paint, or any water stains on the ceiling below the balcony. These are clear indicators that your waterproofing has failed.

2. Water Testing

Perform a water test by spraying your balcony with water. Observe how the water behaves. If it pools or seeps into the surface, it’s a clear sign of waterproofing failure.

3. Professional Inspection

Consider hiring a professional waterproofing expert to conduct a thorough inspection. They can use specialized equipment to detect leaks and provide a detailed assessment of the damage.

Fixing the Leaky Balcony

Now that you’ve identified the problem areas, let’s delve into how to fix a leaky balcony after waterproofing failure:

1. Remove Old Waterproofing

To start the repair process, you’ll need to remove the old, damaged waterproofing material. This typically involves scraping off the existing layers to expose the substrate.

2. Repair Substrate Damage

Inspect the substrate (the underlying structure) for any damage. Replace or repair any weakened or rotten wood, concrete, or metal as necessary. A solid substrate is crucial for a successful waterproofing application.

3. Apply New Waterproofing Membrane

Once the substrate is in good condition, apply a new waterproofing membrane. There are various options available, including liquid membranes, sheet membranes, and peel-and-stick membranes. Choose one that suits your balcony’s specific requirements.

4. Seal Joints and Cracks

Pay special attention to joints, corners, and cracks, as these are common areas where leaks occur. Use a high-quality waterproof sealant to ensure these vulnerable spots are properly sealed.

5. Test for Adequate Waterproofing

Before you consider the job complete, perform another water test to ensure the new waterproofing is effective. Make any necessary touch-ups or adjustments if leaks persist.

Preventive Measures

To avoid future waterproofing failures and balcony leaks, follow these preventive measures:

1. Regular Maintenance

Inspect your balcony periodically for signs of wear and tear. Catching issues early can prevent major waterproofing failures.

2. Proper Drainage

Ensure that your balcony has proper drainage systems in place. Poor drainage can put excess stress on waterproofing materials.

3. Professional Installation

When installing or repairing waterproofing, hire professionals with experience in balcony waterproofing. Proper installation can significantly extend the lifespan of your waterproofing system.


A leaky balcony due to waterproofing failure can be a headache, but it’s a problem that can be solved with the right approach. By identifying the issues, removing old waterproofing, repairing the substrate, applying new waterproofing materials, and taking preventive measures, you can fix your leaky balcony and enjoy a dry and safe outdoor space once again. If you’re unsure about any of the steps, don’t hesitate to seek professional assistance. With patience and diligence, your balcony can be leak-free for years to come.

Don’t let a leaky balcony dampen your spirits; take action today to protect your home and enjoy your outdoor space to the fullest.