How to Repair a Leaking Balcony

by balconyboss
Published: Last Updated on
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Balconies are a wonderful outdoor space that can be used to extend the living area of your home or to create an enjoyable outdoor space where you can sit, relax, entertain friends and much more. However, balconies are vulnerable to certain issues–including leaking. If your balcony is leaking, then you need to address the problem as soon as possible in order to prevent further damage. The following guide will help you understand why balconies may leak and how to repair your own leaking balcony.

Why Balconies Leak

There are several reasons for why a balcony might be leaking. Before you can repair the balcony leak, you’ll need to figure out what is causing the leak in the first place.

One potential reason for a leaking balcony is structural damage. Structural damage can include damage to the balcony’s expansion joints or other integral structural components of the balcony. If you believe the leak is caused by structural damage, you will need to contact a professional.

However, structural damage is not the most common reason why balconies begin to leak. The most common reason why balconies begin to leak are drainage issues or damages to the surface material of the balcony, which causes water to drip onto the balcony or accumulate rather than run-off as it normally would. These issues can be often be repaired without professional assistance, so if the issue appears to be related to drainage issues, then read on to find out how to fix the issue.

How to Repair Your Leaking Balcony

The following are the two primary steps you need to take in order to repair a leaking balcony. However, remember: if you believe the leaks are caused by structural damage, then you will want to bring in a professional to make sure that the job is done safely and the issue is correctly fixed.

For leaking caused by drainage problems however, the following two steps are enough to address the issue.

Assess the drainage issue

The first thing you need to do is address the drainage issue in question. What is causing the drainage issue? Does your balcony have damaged drainage gutters? Is there damage in the concrete flooring of the balcony which is causing water to accumulate rather than run off? Once you know the exact issue that is causing a drainage problem, it can be repaired. For instance, the drainage gutters can be replaced or a hole in concrete can be patched up.

Add water-repellent sealant

Once you have addressed the drainage issue and completed the proper repairs, it is time for the final step that will help reduce leakage-related issues on your balcony in the future. This can be done by applying a water-repellent sealant. This type of sealant will help prevent water accumulation and reduce the chances of your balcony material becoming damaged by water. This is especially important for preventing structural damage, such as damage to the balcony’s expansion joints, which can occur when water is soaked into the material.


Remember to give your balcony a thorough inspection after completing any repairs in order to make sure everything is safe and sound.