Keep Foundations Dry and Protected
 Exterior membranes Services 

Applying a high-quality exterior membrane directly to the foundation wall is one of the most effective ways to stop water before it gets inside. It creates a long-lasting barrier against moisture, soil pressure, and leaks.

We use flexible, high-performance exterior waterproof membranes that can move with your foundation and resist cracking. The best type depends on your home’s structure and drainage, and we always match the product to the job.

When installed correctly, exterior membranes can last 20–30 years or more. At Diamond Masonry & Waterproofing, we only use trusted materials and back our work with warranties for added peace of mind.

The main downside is that it requires excavation to access the foundation walls, but it’s also one of the most thorough and long-lasting solutions. Our team keeps the process clean, careful, and efficient from start to finish.

Exterior waterproofing stops water at the source, while interior solutions manage it after it enters. For long-term protection, exterior membranes are often the better investment, especially if you’re looking to fully prevent water intrusion.

Yes, when properly installed, exterior waterproofing membranes form a protective barrier that prevents water from seeping through foundation walls, even during heavy rain. This is especially valuable in areas like Suffolk and Nassau County where seasonal downpours can lead to water intrusion.

The process typically involves excavating around the foundation, cleaning the surface, applying a waterproof membrane (such as rubberized asphalt or polymer-modified bitumen), and then adding a protective drainage layer. The trench is then backfilled carefully to restore the landscape.

Most residential exterior membrane installations take 2 to 5 days, depending on the size of the foundation, soil conditions, and weather. Larger or more complex projects may take longer, especially if other drainage components like weeping tiles or sump systems are added.

The most common causes include improper surface preparation, membrane punctures during backfilling, and inadequate drainage systems. Over time, poor installation or soil pressure can cause the membrane to separate or degrade, reducing its ability to block water.

While possible, it’s not recommended. Proper installation requires excavation, surface preparation, and understanding of local drainage, all of which involve safety risks and technical knowledge. Our professionals make sure the membrane is applied correctly and lasts.