Is your Builder Serious about Waterproofing?

Why waterproofing is a critical step in the construction of your dream home, and how to go about it the right way.

Waterproofing is one of the most critical, yet one of the least understood concerns when it comes to the checklists that home buyers have. If not in-depth knowledge of concreting technology, you do need to understand its criticality and know the questions to ask your builder to ensure your dream home remains truly waterproof. In this article, we examine waterproofing in detail..

Understanding Waterproofing and the 'Building Envelope'

At its core, waterproofing is the process designed to prevent water from entering into a structure. Typically waterproofing is done in various layers and stages to create a set of barriers such that water cannot penetrate the structure. A structure is waterproofed by the use of membranes and coatings to keep water out of a building while also protecting its structural integrity. A combination of such stages is referred to as creating a “Building Envelope”. This is why the compatibility of materials, their interactions, the interconnectivity of building spaces also become important to the process. Waterproofing is intended to offer protection from weather, seepages from ground while considering the vertical travel tendencies of water in a structure.

Common Mistakes in Waterproofing

Choosing the wrong waterproofing material: Each one of the available waterproofing materials has a specific use case. Choosing the wrong chemical will result in failure sooner or later. For example, waterproofing expansion joints in larger structures require material that should be flexible enough to stretch along with the building. In a composite joint where aluminium meets wood or concrete, you need materials that are compatible with all the surrounding materials.

Faulty External Plastering: If the external plastering of the building envelope is carelessly done, it could result in ingress points for water. For example, the holes provided in the walls for scaffolding are sometimes not filled properly nor corrected after filling.

Incorrect Diagnosis of a Leakage:If leakage is detected during waterproofing, it is critical to diagnose it correctly. The source of the leakage is not always located near the visual marks of it. After entering the body mass, water flows in all possible directions. Diagnosing a leakage correctly is the first step to fixing it.

Lack of Preparatory Work: Preparing for waterproofing is almost as important as the task itself. It involves cleaning the surface to remove dust, filling all the holes, cracks and cavities, repairing the damaged sections, relocating the embedded pipes, among others.

—   NVT Quality Lifestyle has its roots in NVT Quality Certification, one of the most trusted quality certification bodies in the aerospace industry.

Why waterproofing is critical

While it is well known that waterproofing is critical, the reasons why it is so are not as well understood. And while there are several building contractors around the country that claim they specialize in building waterproofing, especially for new construction services, it is important to be on the same page with them about the purpose. From the point of view of a home buyer, building waterproofing is important because:

It’s not just about keeping the building dry: Good waterproofing is not just about preventing seepage into a building, it is also about reducing internal humidity, and making a building more comfortable to work and live in. It protects objects inside the building from damage as a result high humidity such as corrosion of household electronics or other metallic items.

Structural integrity: Water breaks concrete down. Not only does the lack of good waterproofing start looking bad, but it results in the building getting weaker. The concrete erodes, exposing matrix materials and base concrete. When you waterproof concrete you are also protecting the re-bar inside the concrete from rusting and eroding.

Mould and mildew: Good waterproofing prevents mould and mildew and fungal attacks from getting into the walls and floors. This makes waterproofing essential to the health of those who live in the building.

Reduces maintenance costs: With waterproof structures, you have a lot less work to do when cleaning up after a heavy rainstorm. Basic maintenance is much easier when the there is good waterproofing.

Higher property value: Should the time come to sell your property, a waterproofed building is a good selling point. No one wants to buy a house with seepage problems.

Your builders approach to waterproofing must address these reasons to go for waterproofing, not just as a checkbox, but as a core part of the building process.

How the Six-Step NVT Intensive Process ensures high-quality waterproofing

At NVT, we pride ourselves in the superior quality of our waterproofing process. We follow a 6-step intensive process to waterproofing at an NVT QL villa. This is made possible with a strategic partnership with Endura, a German company, worldwide leaders in waterproofing technology.

Step 1- Clean the surface:
As a first step, the loose mortar from the slab is cleared to achieve a clean surface. This is always the first, critical step.

Step 2- Raise the level of the corners to ensure smooth water run-off:
Once raised sealant WPM E135 is applied at the corners to a height of 1.5 feet to prevent any water leakages by creating a smooth surface for the water to run off.

Step 3 - Create ponds on the surface for 48 hrs to check for seepage:
We then create a water pond on the roof and leave it for 48 hours to check for any water seepage.

Step 4 - Apply Ardex WPM 300 as a primer:
Next, we apply WPM 300 as a primer to create an even surface to ensure a strong bonding with the waterproofing chemical.

Step 5 - First layer of waterproofing chemical with a mesh:
We then apply the first coat of the waterproofing chemical, WPM 002, along with a deck web mesh at the corners.

Step 6 - Final layer of the waterproofing chemical:
Finally, we apply another layer of WPM 002 to ensure a perfectly waterproofed surface.

At NVT Quality Lifestyle, our obsession with the highest quality of waterproofing is just one of the many ways we deliver on our promise of building luxury homes for professionals; it is our raison d' être. Being from a professional background ourselves, we make this possible by staying true to our credo - Always Thinking Quality.


NVT is one of the leading Villa developers in Bangalore. Founded by a team of professionals who spent their early years with large multinationals before starting NVT. The founding team is also alumni of some of the most prestigious universities in the world like Carnegie Melon, Purdue, IIT etc.