Epoxy and polyurethane are each resins; generally, they’re component formulations. The blending of the parts for each resin type creates the material with the requisite properties for crack repairs.
Epoxy’s elements are a resin and a hardener; blended collectively before a crack injection. The combo ratio is typically two parts epoxy to 1 part hardener. Injection epoxies typically remedy within three to four hours. Once cured, epoxy has a robust bond and a hard plastic-like texture.
Polyurethane, while not necessarily a component mix, typically has two; one is the resin and the opposite is an accelerator. Unlike epoxy, the texture of cured polyurethane varies significantly; one can’t generalize relating to the properties of cured polyurethane.
Differences in The Epoxy and Polyurethane Crack Injection Processes
There are significant variations in how polyurethane and epoxy crack injections are carried out. Epoxy injections are referred to as “Surface port injections” because they contain the usage of injection T-Ports to inject the epoxy right into a crack.
Polyurethane injection involves much higher injection pressures utilizing packers inserted into drilled holes through the crack within the poured concrete foundation. Like epoxy, the injected polyurethane fills the crack through the whole thickness of the foundation thereby stopping water from getting into the crack. Professional polyurethane crack injections typically contain a flushing process to clean the crack to improve adhesion within the crack.
Advantages of Epoxy Crack Injection
1. The tensile strength of cured epoxy is greater than that of poured concrete. Under rigidity, cured epoxy crack repairs will not yield.
2. Epoxy injections provide positive confirmation to the injection technician that the crack has been fully filled.
3. Epoxy crack injections are extraordinarily reliable as a consequence of their low failure rate.
4. Epoxy’s curing time allows the epoxy to gravity feed within the crack, thereby filling all parts of even the finest cracks.
Advantages of Polyurethane Crack Injection
1. Polyurethane can be utilized regardless of the crack condition and the weather. It doesn’t matter if the crack is actively leaking, filled with mud and/or mineral deposits, or if it is small or large.
2. Polyurethane injection involves a crack flushing process that cleans out the crack prior to the injection.
3. The chemical expansion of the polyurethane will fill voids within the concrete.
4. The speedy curing of polyurethane is useful when speedy waterstopping is required.
Disadvantages of Epoxy Crack Injection
1. Moisture adversely impacts the adhesive qualities of the anchoring epoxy used to adright here the T-Ports onto the crack. Without ample adhesion, the anchoring epoxy will not withstand the injection pressure.
2. Epoxy is inappropriate for re-injecting previously injected crack repairs which have failed.
3. Homeowner basement leak repairs with hydraulic cement or caulking render epoxy injections inappropriate because there isn’t any longer surface access to the crack, mud and/or mineral has constructed-up within the crack, and the concrete around parts of the crack is commonly damaged by water saturation.
4. The curing time and the available viscosities of epoxy are positive attributes, but also weaknesses. Epoxy crack injection depends on the containment of epoxy within a crack till the epoxy has cured. This containment makes use of the compacted soil towards the outside wall. Poor compaction, air-gap membranes and the use of epoxies with inadequate viscosity will end result within the bleeding of epoxy into the soil.
Note: The strong epoxy bond is commonly cited as a negative attribute of epoxy crack injections as a result of its rigidity. Keep in mind that your complete poured concrete foundation is rigid; due to this fact, the necessity for flexibility within the material used to inject a crack, in my opinion, is illogical as there isn’t any real need to accommodate crack movement.