Prepare the concrete (Base Layers)
Seal & bond (Surface Barrier)
Protect & finish (Topcoats & Sealers)
Complete systems (Multi-Layer)
Technical detail (Long Form)
How concrete fails
Concrete rarely fails from the outside in. It fails from a compound its own curing reaction leaves inside it. Here is what that compound is, what it causes, and what converting it changes.
Concrete falls apart from the inside because a large share of its own binder is a compound that carries no load and dissolves easily. When cement hydrates it leaves calcium hydroxide, also called portlandite, as a by-product. Benjamin Cook, Zirconia’s founder, puts it at 20 to 25 percent of the cement, and Zirconia’s chemistry reference puts the leftover at roughly 20 percent of the cement mass. Either way, about a fifth of the binder holding a structure together is soluble and chemically reactive rather than structural. It is what carbonation consumes, what acid dissolves, what soft water leaches out, and what wear removes first. Convert it into a durable binder and the mechanisms that depend on it lose the thing they feed on.
Portland cement does not turn entirely into the phase that does the work. The hydration reaction that builds calcium silicate hydrate, the binder written as C-S-H, also produces calcium hydroxide alongside it. That is inherent to how cement cures, not a sign of a bad mix or a bad pour. It is present in sound, well placed, correctly cured concrete.
This is also why the paste, rather than the aggregate, decides how long a structure lasts. Aggregate is comparatively dense and inert. The paste carries both the capillary pore network and the weakest phase in the matrix, and those two things sit next to each other: the pores deliver water and everything dissolved in it straight to the compound least able to resist it.
Calcium hydroxide is not inert filler quietly taking up space. It is the most chemically available part of the matrix, and that makes it the point of entry rather than a passenger. Three properties do the damage.
Each of those ends the same way. Wherever calcium hydroxide is consumed or washed out, it leaves a void, and that void widens the pore network which delivered the attack. Damaged paste is more porous than sound paste, so every round of damage opens the path for the next. Concrete deterioration accelerates rather than progressing steadily, and this compound is the reason why.
Benjamin Cook counts six separate forms of corrosion that trace back to calcium hydroxide. They look like six different problems on a condition survey. Chemically they are six different aggressors arriving at the same target.
Carbon dioxide diffuses in and reacts with calcium hydroxide, decalcifying the binder and dropping pore pH from about 12.5 to below 9. Below that point the passive oxide film that protects embedded steel dissolves, and reinforcement corrosion begins.
Free calcium hydroxide leaves the paste with a net positive surface charge, which draws negatively charged chloride ions inward. Untreated concrete also lacks the aluminate sites needed to lock chloride away, so it travels through the pore solution to the steel.
In sewers and wastewater structures, bacteria convert hydrogen sulfide into sulfuric acid. That acid attacks calcium hydroxide and the binder, releasing gypsum and silica gel and opening the surface further with every cycle.
Soft water, carbonation and acid all pull calcium out of the binder. Bridging bonds hydrolyze, interlayer water is lost, and what remains is a silica-rich gel with a fraction of the cohesion the original binder had.
Wear removes the weakest phase first, and on untreated concrete the weakest phase is the portlandite-rich paste at the surface. The wear face is the vulnerable material rather than the durable one.
Pore water expands about 9 percent when it freezes. Every void that leaching and carbonation open makes room for more freezable water, so each winter cycle cracks a slightly weaker, slightly wetter matrix than the one before.
Read that list as one mechanism rather than six. Carbonation, chloride attack, acid, wear and freeze-thaw are different aggressors, but they converge on the same soluble, reactive, load-free compound, and each one leaves the concrete more open than it found it. That is the useful way to think about it: treating the symptom means chasing six problems, and treating the cause means changing what the concrete is made of.
What to do about it
Zirconia’s chemistry does not coat calcium hydroxide over or wash it out. It converts it. A colloidal alumina-silicate treatment travels into the capillary network and reacts with the free calcium hydroxide and with the calcium-rich, high-pH pore solution around it, converting the weakest phase of the matrix into calcium aluminosilicate hydrate, or C-A-S-H. The same reaction bonds into the existing binder and upgrades that too.
C-A-S-H is the same basic structure as ordinary C-S-H with aluminum substituted into key positions, and that single change does four things. Chains grow longer and cross-link into a network rather than sitting as separate strands. Calcium locks in more tightly, so it resists leaching. The denser framework slows carbonation. And the aluminate sites give the matrix an active ability to trap incoming chloride as Friedel’s salt, which holds while the alkaline reserve keeps pore pH above 9. This is chemical regeneration of the binder phase, not pore filling with a foreign material.
Benjamin Cook’s own description of the outcome for carbonation is the plainest version of the point: the treatments eliminate the calcium hydroxide, which makes the concrete surface immune to carbonation, because there is no calcium hydroxide left for carbon dioxide to consume.
ActiveCure™ is applied to fresh concrete in the first days after placement, replacing conventional curing with a chemistry that joins the hydration reaction already under way. It converts calcium hydroxide to C-A-S-H as that compound forms, so the slab matures denser and less porous than ordinary cured concrete rather than being treated for its porosity later. On the call of 19 August 2026, Benjamin Cook described it making the concrete seal itself in about 40 minutes, so the pour does not lose its water during the initial cure. Because the matrix is denser from day one, CeramycGuard™ can follow in 5 to 7 days instead of the traditional 28-day wait.
Ceramic System PoreBlocker™ does the same chemistry on concrete that is already in service, often decades old. It penetrates the existing pore network and rebuilds the matrix that age, carbonation and chloride exposure have degraded, converting the free calcium hydroxide it finds and re-forming the bonds that corrosion broke. This is the reason an aged asset has an option other than demolition. In Benjamin Cook’s framing of why it matters commercially, the alternative used to be that people simply demolished the driveway, or the bridge deck, and rebuilt it.
Silicate densifiers also react with calcium hydroxide, but they carry no aluminum, so they rebuild with the weaker C-S-H, reach only a few millimeters, and give the matrix no ability to bind chloride. Silanes and siloxanes line the pore walls to repel water, which is a real effect, but it is an organic chemistry that degrades under ultraviolet light over years while the binder underneath keeps aging untouched. Neither approach converts the compound this page is about. If you want the two chemistries side by side, see colloidal silica versus colloidal aluminate-silicate, and for how the pore network delivers the damage in the first place, see is concrete porous.
The chemistry that results is in the same alumina-silicate family as the pozzolana used in Roman construction, which is where Zirconia’s approach comes from and why the comparison gets made. It is an origin story and not a performance prediction, so we do not attach a lifespan figure to a treated structure on the strength of it. What is measurable is narrower and more useful: the compound that carried no load and fed six forms of corrosion is no longer there to be attacked.
Tell our technical team the age, the exposure and the condition, and they will tell you whether the asset needs the new-concrete chemistry, the penetrating treatment, or the full system.
Common questions
It is a by-product of cement hydration, not an additive and not a defect in the pour. The reaction that builds concrete’s binder leaves calcium hydroxide, also called portlandite, behind it. Benjamin Cook, Zirconia’s founder, puts it at 20 to 25 percent of the cement, and Zirconia’s chemistry reference puts the leftover at roughly 20 percent of the cement mass. Either figure describes the same situation: a large share of the binder in a slab carries no structural load.
Because it is soluble, chemically reactive and soft, so it is the part of the matrix that every aggressor reaches first. Carbon dioxide consumes it, acids dissolve it, soft water leaches the calcium out of the binder, and wear removes it before anything harder. Each time some of it goes it leaves a void behind, and that void widens the pore network that delivers the next attack.
A colloidal alumina-silicate treatment reacts the free calcium hydroxide and the calcium-rich, high-pH pore solution into calcium aluminosilicate hydrate, or C-A-S-H. That is a durable binder phase rather than a soluble by-product, so the compound that was the weakness becomes part of the structure. It is chemical regeneration of the binder, not pore filling, and it also upgrades the existing binder it bonds into.
ActiveCure™ is specified for new concrete. It is applied in the first days after placement and converts calcium hydroxide to C-A-S-H as the concrete cures. Ceramic System PoreBlocker™ is specified for existing concrete, often years old, where it penetrates the pore network and rebuilds the matrix that age, carbonation or chloride exposure has degraded. Same family of chemistry, different stage of the asset’s life.
It changes the chemistry that drives further damage, which is a different job from structural repair. With CeramycGuard™ the system chemically re-bonds cracks up to roughly 5 mm. Wider cracks, actively moving cracks and anything structural still need proper repair first, with the ceramic system applied afterwards as the protective layer.
It is the same chemical family. Zirconia’s chemistry is an alumina-silicate geopolymer, related to the pozzolana used in Roman construction, and that lineage is where the approach comes from. It is an origin story rather than a performance prediction, so we do not attach a service-life figure to it.
Talk to our technical team about the right ceramic surface treatment for your concrete infrastructure.