Two distinct chemistries, one diagnosis. Polyurethane expands when water touches it, sealing active leaks from inside the crack. Epoxy bonds dormant cracks back to monolithic strength. We assess the crack first, then inject the right Sika product at full depth. No guessing, no failed repairs.
Why Sika Crack Injection Requires the Right Product
Not all cracks are the same, and not all injection materials work on all cracks. A wet, actively leaking crack needs polyurethane because the water itself triggers the chemical reaction that makes the material expand and fill the void. Epoxy cannot cure in the presence of water; it will fail on an active leak. Conversely, epoxy is the structural choice for dry, dormant cracks where the goal is to restore the slab to monolithic strength.
We start every job by classifying the crack: Is water present? Is the crack moving or stable? Does it carry structural load? Once we know the answers, the chemistry choice is clear. Sika offers both in injection-grade formulations with the ports and equipment needed for controlled, full-depth delivery.
See our broader Sika waterproofing work for foundation protection, and basement concrete solutions when the crack is part of a larger water-management strategy. For structural assessment, consult foundation repair guidance.
Recent work
The injection sequence
How Sika Injection Gets Done in Regina
Assess the crack condition
We examine the crack for water presence, movement, depth, and structural role. This assessment determines whether polyurethane or epoxy is the right choice.
Prepare and port the crack
The crack surface is cleaned and sealed with paste between injection ports. Ports are spaced according to Sika specifications for the chosen chemistry and crack geometry.
Inject under controlled pressure
Sika polyurethane or epoxy is pumped through each port in sequence at the pressure needed to reach full depth without forcing material into surrounding concrete.
Cure and finish
The material cures (polyurethane fast, epoxy over several days), ports are removed, the surface is sealed, and the repair is verified for complete fill.
For active leaks
Polyurethane Injection Stops Water Now
When water is actively flowing or seeping through a crack, epoxy will not work. The water prevents epoxy from curing and bonding. Polyurethane is engineered for this exact scenario. The water in the crack triggers the polyurethane to expand, filling the void and bonding to the wet concrete surface. The leak stops during injection, not weeks later.
This is the standard choice for basement walls with active seepage, foundation cracks that weep after rain, and any slab crack where moisture is present at the time of repair. Pair with Sika floor systems if surface restoration is needed, and review basement waterproofing for the broader moisture strategy.
Polyurethane vs epoxy, active leaks, port spacing and structural restoration.
Polyurethane for active wet cracks (it reacts with water to expand and bond), epoxy for dormant dry cracks that need structural restoration (it bonds the crack sides permanently). The wrong chemistry fails immediately.
Yes, polyurethane is specifically designed for this. The water in the crack triggers the polyurethane reaction, the material expands to fill the crack, and the leak stops.
Yes, with epoxy. Properly injected epoxy restores the two sides of the crack to monolithic strength. The crack itself becomes structurally stronger than the surrounding concrete in many cases.
Based on crack width, depth, and the chosen chemistry's flow characteristics. Sika specifies port spacing per product; we follow the spec so material reaches full-depth without gaps.
Most residential crack injections are a single-visit job, a few hours from port install through cure. Large structural projects with many cracks stretch over days. The schedule is in the quote.
Polyurethane injection on an actively leaking basement crack. Water stopped during injection, dry for two years since. The right chemistry made the difference.
Q. Y5
Property Owner, Regina
★★★★★
Epoxy injection for structural restoration on a foundation crack. Test cores after cure showed the crack zone stronger than surrounding concrete. Real structural repair.
Y. Y5
Engineer, Regina
★★★★★
Multiple cracks across a structure, each classified properly and injected with the right chemistry. The discipline of product-per-crack-condition is rare and showed in the result.
Z. Y5
GC, Emerald Park
★★★★★
They diagnosed an injection that another contractor had failed on. Used the right Sika polyurethane this time; held through three winters. Crack chemistry matters.
X. Y5
Builder, White City
From the blog
Concrete Guides & Articles
Practical reading on planning, finishes and caring for concrete in Regina.
Describe the crack (wet or dry, moving or stable, structural or cosmetic) and we will recommend the matched Sika chemistry and provide a written estimate.
