Stop Balcony Leaks! Get the Pro Guide

The Big Takeaway

Even if it’s below a roof, balconies are still exterior surfaces. That means they require special treatment to keep out the elements and avoid leaks, rot, and costly repairs.
Most balcony leaks come from a mix of an inadequate slope, cracked surfaces, and missing or damaged flashing, not just from bad weather.
When installed and maintained correctly, a properly waterproofed balcony can withstand decades of harsh and mild weather.

In previous series, we’ve presented houses as systems of interdependent parts. You could have the strongest roof on the market, but if your flashing[LINK Flashing A1] is off or your sealant[LINK Sealant A1] is incorrect, the roof won’t matter. Rain will seep through cracks and joints, rotting the structural components that hold up your roof and leaking down into your home. That trapped water leads to rot, rust, and mold long before you ever see a stain.

Texas weather makes this worse. The mix of heat and cold swings, UV radiation and hail impacts, and sudden downpours wears down and puts under high stress the components of a roof system. These same waterproofing principles hold for balconies. Just because some balconies are tucked under roofs doesn’t mean they aren’t external surfaces. They still need to be properly cared for, to be treated as a system, and as part of your broader home’s system. We’ll take a closer look at what homeowners need to know about balcony waterproofing in this article.

Why is My Balcony Leaking?

Waterproofing means building a barrier that keeps water out and routes it away from your home’s surfaces and into a safe place for its absorption. Most balcony leaks come from shortcuts taken during construction. We’ve talked at length about Texas’ underregulated roofing market[LINK], which puts homeowners at risk of paying for a quality of service they may not receive, and not knowing until it’s too late.

Construction shortcuts can include the use of cheap or improper materials, creating a surface slope that isn’t adequate to shed water, or improperly placing flashing along the wall and joints or missing flashing altogether. Materials like tile or concrete, when they crack, can also let water in, and coatings that aren’t made for sun and foot traffic will quickly dry out, peel, and stop protecting the surface.

Once water gets underneath your balcony, it stays there. In wood decks, that means swelling and rot. In concrete, it leads to rusting steel reinforcement. Either way, the damage compounds largely outside of view. In other words, balcony leaks don’t just come from a single storm. It indicates that there are deeper waterproofing issues at play that must be addressed to prevent deeper structural damage.

How to Waterproof Your Balcony

Waterproofing balconies is best handled by professionals, but for DIY-minded or curious homeowners, let’s take a look at the process. Several components work together to keep water out: a primer bonds to the surface, a reinforced membrane creates a tighter seal, a wear coat protects them from foot traffic, and a topcoat protects against sun and weather. The surface itself must be sloped in such a way that it drains water and prevents pooling.

The types of products used should be matched to the material of your balcony, flex with the structure, handle heavy use, and meet building codes. For instance, wood will require a different treatment than concrete. Then comes upkeep. Drains must be kept clear from debris clogs, chips and cracks must be repaired as soon as they appear, and topcoat should be reapplied every few years to protect against UV damage. This will keep your balcony waterproof for years to come.