Concrete Crack Injection

What we treat

We inject cracks in concrete structures on industrial sites, to restore watertightness or, when the structural specialist's specification calls for it, to rebond the concrete.

• Basins and containment: process basins, secondary containment around tanks, containment pits.
• Sumps, pits and chambers: pump sumps, valve chambers, equipment pits.
• Equipment foundations: bases for pumps, compressors, mills and machinery.
• Industrial slabs: cracked production and warehouse slabs before a floor coating is installed.
• Plant foundation walls: water seeping through cracks and cold joints.
• Water treatment structures: settling basins, channels, concrete tanks, pumping stations.

The service is for industrial, municipal and commercial structures; we do not repair house foundations. Work is carried out by our crews and qualified subcontractors, under one quote and one inspection file.

Epoxy or polyurethane: when to choose each

The product is chosen from the condition of the crack: dry or wet, dormant or active. The ACI 224.1R guide is the framework for evaluating the crack and selecting the repair.

• Epoxy injection: for dry, dormant cracks. The rigid resin fills the crack and bonds both faces back together. Structural rebonding is done only to the client's structural specialist's specification; the resin meets ASTM C881 and the work follows the ACI 503.7 specification.
• Hydrophobic polyurethane injection: for wet or leaking cracks. The resin reacts with water, expands into foam and stops the flow. It provides watertightness, not strength.
• Hydrophilic polyurethane injection: for cracks that stay wet and move slightly. The product absorbs water and stays flexible.
• Active cracks: a crack that opens and closes with temperature or load cannot be rebonded with epoxy, which would crack alongside. Watertightness is restored with a flexible polyurethane, or the crack is treated as a joint.

Selection among leak-sealing grouts follows the ICRI 340.1 guideline. The manufacturer's data sheet sets each product's limits: crack width, temperature, moisture.

How an injection job runs

A crack injection job follows six steps, from the survey to the finish.

• Survey: crack mapping, width, length, presence of water, rust staining. Tell-tales placed across the crack show whether it moves.
• Injection ports: surface-mounted ports for epoxy, or angled drill holes that intersect the crack inside the concrete for polyurethane.
• Surface seal: epoxy paste over the crack between ports, to keep the resin inside the concrete during injection.
• Low-pressure injection: from the lowest port upward, or from one end to the other, until resin appears at the next port.
• Check: verification of fill, water test for watertightness and, when the quote calls for it, test cores per ACI 503.7.
• Finish: ports and paste removed, surface ground, patched with mortar where needed.

Inspections and standards

The close-out file documents every crack treated. The following references frame the work:

• ACI 224.1R: causes, evaluation and repair of cracks in concrete structures.
• ACI 503.7: specification for crack repair by epoxy injection, including test cores.
• ICRI 340.1: selection of grouts to control leakage in concrete structures.
• ASTM C881: requirements for epoxy resins used with concrete.

The file includes the crack map, the resin used and its batch numbers, injection conditions (concrete and air temperature), quantities injected per zone, water test results and before and after photos.

Limits: structural cracks

A structural crack is assessed by the client's structural specialist before any injection. Injection treats the crack; it does not correct its cause.

• A crack that runs through a load-bearing element, keeps widening or comes with deformation: assessment is required before any work. We then inject to that specification.
• Rust staining or spalled concrete along the crack: the rebar is corroding. Injection alone is not enough; the concrete needs repair.
• A cause that is still active (settlement, overload, vibration, frost): the crack will return unless the cause is dealt with.

We do not perform structural assessments. We report what the survey shows and wait for the specialist's opinion before injecting a doubtful crack.

Site conditions and safety

We fit the method to the structure and its operation; these conditions are settled in the quote.

• Basins in service: polyurethane often allows a leaking crack to be injected from the dry side without fully draining the structure. Epoxy needs a dry crack, so the structure must be drained and dried.
• Confined spaces: sumps, chambers and empty basins follow the site's confined space entry procedure, with ventilation, gas detection and an attendant. In wastewater, H2S is checked (H2S concrete corrosion).
• Operating plant: work by zones, with pumps and adjacent equipment locked out.
• Winter: concrete and resin must stay within the data sheet's application range; a heated enclosure is sometimes needed.
• Products: safety data sheets on site, protective equipment, resin waste collected.

Pricing: by quote

Concrete crack injection is priced by quote, because the cost depends on the cracks and the structure. Five factors drive it:

• Total crack length and width.
• The resin: rebonding epoxy or leak-sealing polyurethane.
• Water: active leak, structure full or drained.
• Access: at height, in a confined space, inside a basin.
• The work window: operating plant, shutdown, winter.

Send photos of the cracks, their approximate length and the location with your quote request: we reply within 24 business hours.

Where we work

Induscoat provides concrete crack injection in Montreal, across Quebec and in Ontario, working from LaSalle:

• Montreal and Montérégie
• Quebec, for the province as a whole
• Abitibi-Témiscamingue
• Côte-Nord
• Saguenay–Lac-Saint-Jean
• Mauricie–Centre-du-Québec
• Ontario

After injection, and when it is not enough

Injection closes the crack; it does not protect the rest of the surface. Concrete exposed to chemicals, aggressive water or salts keeps deteriorating around the repaired crack.

After injection, a concrete protection coating seals the surface: epoxy or novolac epoxy in containment basins, a floor coating on slabs (industrial epoxy flooring). System selection falls under our protective coatings work.

Injection is not the right answer when the concrete is spalled, crumbling or attacked deep, or when rebar is exposed: the concrete must be rebuilt first, then protected. The survey settles it.

Typical Problems We Solve

• Water seeping through cracks in walls, basins or pits
• Containment basins that no longer hold their contents
• Cracked slabs to repair before a floor coating
• Cracks in equipment foundations exposed to vibration

What You Receive

• Crack survey and map with width, length, moisture and movement observations
• Technical quote stating the resin per crack type, the method and the planned checks
• Low-pressure injection to ACI 503.7 or ICRI 340.1, ports removed and surface finished
• Close-out file with resin batch numbers, injection conditions, quantities per zone, water test results and photos

Timeline

Standards & Certifications

• ACI 224.1R: causes, evaluation and repair of cracks in concrete structures
• ACI 503.7: specification for crack repair by epoxy injection
• ICRI 340.1: selection of grouts to control leakage in concrete structures
• ASTM C881: epoxy-resin bonding systems for concrete

Industries We Serve

• Water and wastewater treatment: basins, channels, pumping stations
• Mining: process basins, sumps, equipment foundations
• Energy: containment areas, pits, foundation walls
• Chemical and processing plants: secondary containment, slabs, trenches

Service FAQ

Technical guides

• Concrete secondary containment coatings
• Wastewater concrete corrosion and H2S linings
• In-place coating of in-service equipment
• Coating failure modes: diagnosis and repair

Related applications

Concrete industrial use cases where this service is applied.