The ArmorThane system
A disciplined inspect, prep, spray and cure process that turns a failing concrete manhole into a seamless, monolithic structure — usually in a single visit.
The process
The chemistry is fast. The discipline is what makes it last.
01Step 1
A trained crew documents the structure’s condition — corrosion depth, cracks, active leaks, missing mortar, chimney and frame condition — often using MACP-style coding. That record drives the repair plan and liner thickness.
02Step 2
Everything the liner bonds to has to be clean and sound. Crews remove debris, grease and soft concrete with high-pressure water and/or abrasive blasting, stop active leaks, and rebuild voids so the surface is ready to coat.
03Step 3
A primer such as ArmorPrime promotes adhesion to the concrete. Then the applicator sprays ArmorLine polyurea from the bench up through the chimney, building a uniform, seamless membrane — typically 100–250 mils on the walls.
04Step 4
Polyurea gels within seconds and is hard to the touch in minutes. The crew checks thickness and continuity, documents the finished work, and the structure goes back into service — usually the same day.
The liner build
Tap a layer to see what it does.
Layer 5 of 5
Where color, UV stability or added chemical resistance is specified, a topcoat such as ArmorCoat can be applied over the liner. Many manhole specs go without it.
Layer 4 of 5
The structural barrier. A fast-setting, high-elongation polyurea sprayed seamlessly from bench to frame — typically 100–250 mils — that isolates the concrete from acid, gases and groundwater.
Layer 3 of 5
Penetrates and seals the prepared concrete and promotes adhesion between the substrate and the polyurea, reducing outgassing and pinholes.
Layer 2 of 5
Active leaks are stopped, voids and spalls are rebuilt with repair mortar, and benches and inverts are reshaped so the liner goes on over a sound, continuous surface.
Layer 1 of 5
The existing structure, cleaned to sound material by high-pressure water and/or abrasive blasting. Everything above depends on this step.
Compare
| Feature | Our pick Spray polyurea ArmorThane system | Cementitious liner Spray or troweled mortar | Epoxy coating Spray or roll applied | Full replacement Excavate and reset |
|---|---|---|---|---|
| Seamless, jointless barrier | Yes — monolithic membrane | Can crack over time | Yes, when fully cured | Joints between sections |
| Return to service | Same day | Typically after cure time | Hours to overnight | Days to weeks |
| Flexibility / crack bridging | High elongation | Rigid | Rigid to semi-rigid | New concrete, rigid |
| H2S / acid resistance | Excellent | Varies by mix | Good to excellent | Bare concrete is vulnerable |
| Excavation required | No | No | No | Yes |
| Street & traffic disruption | Minimal | Moderate | Moderate | Significant |
General comparison for typical concrete manholes. Actual performance depends on product selection, surface preparation, application and site conditions — always follow the project specification.
Quality control
Owners and engineers want proof. Building QC into every job is how applicators win repeat municipal work.
Wet-film and dry-film measurements confirm the liner meets the specified build.
Spark (holiday) testing finds pinholes and thin spots so they’re fixed before the crew leaves.
Pull-off tests verify the bond between liner and substrate when the spec calls for it.
Before, during and after photos plus job records give owners a clean audit trail.
FAQ
A polyurea liner is primarily a protective barrier: it stops corrosion and infiltration and restores the surface. Structures with significant structural loss may need repairs or a structural design before lining — the inspection step determines that.
No liner bonds well to running water. Active leaks are stopped first with appropriate leak-control products, then the surface is prepared and coated.
Yes. Brick manholes are cleaned, missing brick and mortar are repaired, and the liner is applied over the restored surface to bind and seal it.
Properly applied polyurea manhole coatings are designed for long service life — typically multiple decades — when installed over a well-prepared surface to the specified thickness.
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