Concrete’s Silent Killer

Understanding The Long-Term Cost of Carbonation

For over 100 years, the core chemistry behind PRO Tek Concrete has been trusted to protect infrastructure worldwide. Based on proven sodium silicate science, our advanced formula has been specially modified to meet today’s challenges—especially the often-overlooked problem of carbonation. Unlike regular sodium silicate products that can cause carbonation, our proprietary modified sodium silicate penetrates deep into the concrete matrix, keeping the concrete alkaline, forming a permanent crystalline matrix which helps to waterproof, densify and fortify concrete.

What Is Carbonation and Why Does It Matter for Concrete?

Carbonation is a natural chemical reaction that occurs when carbon dioxide (CO₂) in the air penetrates the pores of concrete. Once inside, it reacts with calcium hydroxide to form calcium carbonate. While this might sound harmless, it slowly reduces the concrete’s natural pH from ~12.5 (strongly alkaline) to below 9.0. This pH drop creates a perfect environment for corrosion to begin—particularly in reinforced concrete where steel rebar is used.

When pH drops too low, the protective layer around steel reinforcement dissolves, allowing moisture and oxygen to trigger corrosion. Over time, rusting steel expands, causing cracks, spalling, and eventual structural failure.

How Should Concrete pH Be Maintained?

Healthy concrete should maintain a pH of around 12.5. This highly alkaline environment is essential because it passivates (protects) the steel inside, keeping it from rusting. When carbonation occurs, that protection is slowly stripped away. That’s why maintaining—and restoring—alkalinity is so crucial, especially in exposed or aging concrete structures.

Infographic explaining carbonation in concrete, showing how carbon dioxide enters the surface, reacts with calcium hydroxide, and forms calcium carbonate. Highlights how this reaction lowers the pH and increases risk of rebar corrosion.

How PRO Tek Concrete Is Different

PRO Tek Concrete modified sodium silicate formula penetrates deep beneath the surface. It reacts chemically with free lime and moisture to form a durable, crystalline structure that densifies the concrete and buffers against carbonation. This ensures long-lasting protection, stabilizing internal pH and extending the life of the structure.

Our formula doesn’t just seal—it transforms the concrete’s internal chemistry. It fortifies and strengthens, protecting against corrosion and enhancing durability for decades.

How Do You Know If Your Concrete Has Carbonation?

Measuring pH is essential to understanding the health of concrete. Here are three common methods to test it:

• Phenolphthalein Spray Test: Fast and easy. When sprayed on a freshly broken concrete surface, it turns pink if the pH is above 10. No colour? That means carbonation has occurred.

• Pore Solution Extraction: This involves crushing a concrete sample, mixing it with distilled water, and using a digital pH meter. It’s more accurate but requires lab access.

• Embedded pH Sensors: Installed during construction or retrofit projects, these sensors track pH changes over time. They're precise, but more costly.

  
  

If pH is already too low, it means corrosion has likely started. Repairs at this stage can be invasive and expensive—which is why preventative treatment is key.

Infographic showing three methods to test pH in concrete—spray test, pore extraction, and sensors—highlighting how each detects carbonation risk and helps prevent rebar corrosion.

The PRO Tek Concrete Advantage: Modified Sodium Silicate

With a history of over 100 years, our time-tested formula uses a modified sodium silicate—scientifically engineered to do what others can’t. It’s not just a surface fix; it’s deep-level protection.

Here’s what makes PRO Tek Concrete different:

• Penetrates deeply to react far below the surface

• Neutralizes excess calcium hydroxide, stopping carbonation at the source

• Densifies and reinforces the concrete matrix

• Restores alkaline conditions to protect rebar from corrosion

  
  

In short, it doesn’t just seal—it strengthens, waterproofs, and fortifies. It doesn’t just block moisture—it rebuilds concrete’s natural defense system.

Why It Matters

Ignoring carbonation is like ignoring a slow leak in your roof—it won’t stay hidden for long. As concrete continues to absorb CO₂ and lose pH, it moves closer to a tipping point where corrosion and structural damage become unavoidable.

That’s why PRO Tek Concrete blends over a century of proven chemistry with modern innovation. By stabilizing pH and reinforcing the internal structure of concrete, our product provides long-term durability that surface sealers simply can’t match.

Looking for Long-Term Protection?

Don’t wait for cracks and corrosion to appear. PRO Tek Concrete works from within to fortify your investment, backed by over a century of proven science and modern innovation. It’s the smartest way to protect your concrete today and for years to come.

Contact us today to learn how PRO Tek Concrete can help you fortify, future-proof, and extend the life of your concrete—before damage ever begins.