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Polyurea Concrete Crack Injection

 

 

Most homeowners best identify concrete cracks in their basement, either on the foundation wall or floor. They may also recognize cracks on the garage floor, patio, or in-ground pool. While concrete cracks might appear to be typical, it is not recommended that they remain neglected.

Foundation and slab cracks are not only an eyesore, but they may hinder the home's value. These cracks, generally due to drying shrinkage, thermal movement, or other causes, usually are nominal and result in a few issues. However, a foundation crack will often widen over time and result in water seepage or possibly the loss of structural integrity.

Fortunately, there is an easy way to permanently repair these cracks without the need for expensive and disruptive excavation or drain tile. Poured foundation cracks may be repaired using the injection of one or two-part flexible polyureas suitable for such repairs (we would recommend either ArmorDeck or SureGrip).

A certified ArmorThane applicator may complete the application of such materials in as little as an hour or more.

HOW CRACK INJECTION WORKS

Most basements eventually leak. The crack injection has been an official way of tackling these repairs for many years throughout the US. More and more foundation repair contractors around the country are adopting the technique because it is cost-effective, reliable, and permanent. The crack injection will fix the problem more than 99% of the time. Even if a crack is not leaking now, eventually, water will find it. The whole objective is to fill the crack with Polyurea from front to back. 

EPOXIES VS. POLYUREAS

The old way of doing these repairs was with the use of Epoxy. Epoxies can sometimes work; however, there are some major disadvantages. 

So you may be wondering, which material is better for repairing concrete cracks: Epoxy or Polyurea? 

Here's a look at the advantages and limitations of each material.

Epoxies

Epoxies for crack injection are available in various viscosities, from ultra-thin to paste-like, to accommodate cracks of different widths. However, epoxies cure very slowly, generally taking hours to harden. This can be an advantage because it allows time for the Epoxy to flow into even the smallest crevices. On the other hand, it's also possible for the Epoxy to flow out of the backside of the crack before it has hardened if the backfill outside the wall has separated from the foundation. The other major issue with Epoxies is their extreme brittleness. The Epoxy tends to crack instead of giving when there is any movement.

Often, there are voids behind cracks due to soil erosion or poor compaction. That's why the crack is leaking in the first place; it's easy for water to enter.

Polyurea

Strength & Flexibility

Polyurea is 4x stronger than Epoxy. It is also 98% more flexible than Epoxy. The flexibility of the material makes it extremely durable and long-lasting. Since the material is flexible, it will not crack or peel, unlike Epoxy.

Polyurea and Urethanes are great for crack filling. Because polyureas' elastomeric nature can accommodate concrete movement, the seal stays intact and does not crack or break off. They also begin to harden within minutes of injection. This reduces the chances of the material flowing out of an injected crack while still in liquid form, and even if some do leak out, the Polyurea will fill the void. 

Application temperature

Freezing temperatures will prevent epoxies from completely curing. Only use epoxies when the installation temperature is above 32 degrees F.

On the other hand, Polyureas will thoroughly cure even in freezing temperatures. Polyureas can cure at temperatures as low as -20 degrees F (-29 degrees C). This gives them the advantage over epoxies.

Appearance

Both filler types will discolor when exposed to UV radiation from sunlight or even some types of interior lighting. UV stabilizers can be added to our polyurea products to delay the onset of any discoloration.

With all the information in front of you, it's easy to see why most people have turned away from epoxies and employed the use of Polyurea instead. If you would like to know more about our products, please fill out a form here and let us know how we can help.