Understanding CreteDefender P2
How and Why CreteDefender P2™ Works
CreteDefender Permanent Protection (“P2”) is a full strength, ready-to-use formulation of
reactive silicates and surfactants that are carried in solution with water. When applied to
concrete, a chemical reaction occurs which hardens, densifies, and prevents the penetration of
water and other chemicals in concrete. CreteDefender P2 will, when properly applied, eliminate
dusting, scaling, and efflorescence, prevent damage due to salts, sulfates, acid rain, and freeze/
thaw cycles, and significantly reduce chloride intrusion thereby inhibiting corrosion of steel
Preventing Concrete Damage:
The structure of the concrete, if you were to look at it under a microscope, would show
aggregates, cement paste (CSH and very small aggregate particles) and a network of tiny air
voids and capillaries. These voids and capillaries are what allow water and other chemical
compounds to enter into the concrete. These compounds either expand and create pressure to
break the concrete, or deteriorate the concrete through acidic reactions.
In order to prevent damage, it is critical to stop access to the pore and capillary structure of the
concrete. Most sealers do this by creating a thin membrane on the surface of the concrete that
will wear out over time. Other sealers repel water and become ineffective in a few weeks to a few
years. CreteDefender P2 is unlike these types of products.
The key to preventing damage and creating durable concrete is to create a dense, impervious
structure in the concrete. This is accomplished by creating a very small pore and capillary
structure in the concrete and/or permanently filling and sealing that structure. The addition of
Supplemental Cementatious Materials, such as fly ash, silica fume, or slag in the concrete mix,
begins to create a much denser concrete with a small pore structure. However, even these
additions do not create a pore and capillary free concrete.
CreteDefender P2 works by entering the concrete’s pore and capillary structure and filling and
sealing this structure with the same elements that occur naturally in concrete. By filling and
sealing the pore and capillary structure, the concrete becomes extremely dense and impervious.
In addition, once inside the structure of the concrete, CreteDefender P2 becomes a permanent
part of the concrete and cannot be removed or worn off.
The Chemistry of CreteDefender P2:
CreteDefender P2’s chemical reaction is completely natural to concrete. When concrete is
mixed, portland cement is hydrated with water, and a reaction takes place that creates heat,
Calcium Silicate Hydrate (CSH), Calcium Hydroxide (lime), and water. CSH is the compound
that gives concrete its stability, density, strength, and hardness. Lime is a by-product of the
hydration process, and is frequently called “free lime” since it is an unused by-product.
When applied to concrete, CreteDefender P2 reacts with the free-lime in the hardened concrete
to create Calcium Silicate Hydrate (CSH), Sodium Oxide, and water. The CSH created in this
chemical reaction fills the pore and capillary structure of the concrete, making a much denser
and more impervious concrete.
Sodium Oxide, the other byproduct of the reaction of concrete and CreteDefender P2, raises
the pH of the concrete, thereby slowing the carbonation process and neutralizing any acidic
reactions that may be taking place.
The reaction of CreteDefender P2 in concrete takes approximately 75 days to complete, but
protection of the concrete is effective within 24 hours of application.
Depth of Penetration:
The surfactants in CreteDefender P2 allow the solution to migrate deeper into the concrete than
water alone. The exact depth of penetration is dependent upon the porosity of the concrete and
the amount of P2 used in the application. In highly dense concrete, P2 may penetrate 1-2 cm
(1/2 inch), while in more porous concrete, 8-10 cm (3-4 inches) is possible. Generally,
CreteDefender P2 will penetrate about 1-2 cm (1/2 inch) deeper than water would penetrate the
untreated concrete. This creates sufficient protection both to the concrete and the reinforcement.
CreteDefender P2 is really permanent:
CreteDefender P2 is permanent. The reaction takes place inside the matrix of the concrete and,
when complete, becomes a permanent part of the matrix. It cannot be removed or worn off.
Since the product of the reaction is CSH, which is natural to concrete, the bond created cannot
be removed except by destroying the concrete.
Application is easy, but the method is critical to success:
CreteDefender P2 works differently than any other coating or sealing product. Due to the way it
works, you need to suspend what you know about how sealers or coatings are applied and what
you can expect to see once applied. Most sealers and coatings require a specific application rate
or thickness. This requirement allows for the establishment of a membrane or a water repellant
seal. CreteDefender P2 does not form a membrane or repellent seal. It seals the pore and
capillary structure inside the concrete mass. Therefore, P2 requires direct contact with concrete
in a way that allows it to be absorbed into the pore and capillary structure. Proper application is
critical to achieve the protection CreteDefender P2 provides.
P2 must be applied to broom finished concrete by saturating the surface of the concrete
sufficiently so that the concrete stays wet (not damp) for 20-30 minutes. A minimum of two
applications is required for all exterior surfaces. When estimating how much material you will
need, we generally recommend one gallon for every 120 to 150 square feet (approx. 1 liter per 3
square meters) for each application. However, this is not a “target coverage rate,” but merely an
estimate for ordering roughly the right amount of CreteDefender P2. The amount you ultimately
use may be substantially more or less than that amount, since coverage is entirely dependent on
the air temperature, humidity, and the porosity of the concrete. Saturation is key, since you are
wanting CreteDefender P2 to penetrate into the pore structure as deeply as possible.
For interior, machine troweled surfaces, the surface must remain wet for 40 minutes. Only one
application is required for these smooth surfaces. However, you should agitate the surface with a
stiff broom or scrubber to help the P2 begin reacting down into the concrete.
You will use less CreteDefender P2 if you apply it out of direct sunlight during the coolest part of
the day (early morning or night-time is the best). The most effective methods for application are
a low-pressure “garden sprayer” or a water pump with a garden hose and “rain shower” nozzle.
On level surfaces, pouring CreteDefender P2 directly onto the concrete and spreading it with a
push broom is also very effective.
Care should be taken to remove any puddles or areas where CreteDefender P2 is standing after
the saturation period by pushing the excess material onto areas that have become dry with a
broom or squeegee. If puddles of CreteDefender P2 are left to harden, a hard, white crystal is
left behind. Crystallized P2 may have to be removed by burnishing stones, so it is important to
remove any puddles of wet CreteDefender P2 during application.
What you will (and won’t) see:
It is important to note that CreteDefender P2 is not a water repellant. It will not make water
“bead” on the surface or have any visible effect on the surface of the concrete. Concrete treated
with P2 may turn slightly darker, but it should not be noticeable if the entire area is treated.
Otherwise, there is normally no visible evidence on the surface of the concrete after
CreteDefender P2 has been applied.
It is possible that, when applied to older concrete, salts or other impurities that are inside the pore
structure of the concrete may be forced out, leaving a white crystalline substance on the surface.
These crystallized impurities can be removed with a strong pressure washer. In concrete that has
high iron content in the aggregate, CreteDefender P2 may turn the concrete brown. However,
this coloration will dissipate with time (usually about a year).
Quality Concrete is necessary:
CreteDefender P2 is only effective on properly mixed and properly placed concrete. This means
that P2 is effective when applied to concrete that has a maximum water to cement ratio of .5:1,
that is properly consolidated at placement, and that has been finished so that air is not entrapped
at the surface. We highly recommend the use of a plasticizer in the formulation of the concrete
mix. The use of a plasticizer increases the workability of the concrete without increasing the
water past the maximum water/cement ratio. CreteDefender P2 is equally effective on air-entrained
concrete and non-air-entrained concrete.
CreteDefender P2 will not be effective on pervious concrete or on masonry products, such as
cinder blocks, CMU’s, or bricks. Additionally, P2 will not make good concrete out of bad
concrete. It will make good concrete extremely durable and long lasting.