Use Mapei Mapeproof Swell for: sealing confined joints, cracks, and penetrations in reinforced concrete where watertight, pressure-resistant performance is critical.

Mapei Mapeproof Swell: A Technical Overview

Mapei Mapeproof Swell is a one-component, hydro-expansive hydrophilic sealant paste supplied in 320 ml cartridges. It bonds to clean, slightly damp concrete and expands ≥100 % on contact with water. When properly confined, it forms a tough, elastic seal that resists hydrostatic pressure, making it ideal for pipe sleeves, cold joints, formwork spacers, and service outlets.

≥ 100 %
Volumetric Expansion in Water

Core Features & Specifications

  • Hydro-expansive seal: minimum 100 % swelling actively fills voids for leak-tight joints.
  • High elasticity: > 700 % elongation flexes with concrete movement without cracking.
  • Mechanical strength: Shore A 32, tensile 2.5 N/mm², tear strength 10 N/mm — stays secure under pressure.
  • Application-ready paste: thixotropic, smooth extrusion bead (6–13 mm) for precise installation.
  • Moisture-tolerant: bonds to clean, slightly damp substrates — no delays waiting for full drying.
  • Controlled curing: skin forms 180–200 min, cures ~ 2 mm/9 h at 23 °C & 50 % RH.
  • Long shelf life: 12 months at +15 °C to +25 °C in unopened cartridges.

The Mapei Mapeproof Swell Advantage

  • Professional leak control that stands up to hydrostatic pressure.
  • Minimises call-backs by stopping water tracking and seepage first time.
  • Fast, neat application — saves time on-site and reduces labour costs.
  • Durable, non-corrosive and insoluble for long-term protection.

Proactive Troubleshooting

Scenario: Applied Without Confinement

Potential Outcome: Bead expands outward, debonds or extrudes, causing leaks.

Adheseal Best Practice: Always apply in a rebate, chase or groove and confine with mortar or concrete to ensure hydrostatic performance.

Scenario: Dirty or Weak Substrate

Potential Outcome: Adhesion fails and water bypasses the bead.

Adheseal Best Practice: Mechanically clean, degrease with ethanol if required, and apply only to sound, slightly damp surfaces.

Applications in Practice: Trade Scenarios

For Waterproofers: Pipe Penetration Sealing

The Professional's Challenge

Water leaks along pipe sleeves causing site delays and callbacks.

The Adheseal Solution

Cut a rebate around the pipe, extrude a 6–13 mm bead of Mapei Mapeproof Swell, then backfill to fully confine. Hydro-expansion ensures a pressure-rated seal.

Best Practice Note

Degrease metal pipes, tool bead evenly, and ensure complete confinement to avoid extrusion.

For Remedial Contractors: Cold Joint Repair

The Professional's Challenge

Live leaks through construction joints where direct sealant placement is not possible.

The Adheseal Solution

Stop flow with a fast-setting plug, chase joint to ≥ 6 cm depth, extrude Mapei Mapeproof Swell, and confine with repair mortar both sides.

Best Practice Note

Compact mortar well to eliminate voids and maintain a continuous barrier against water ingress.

For Pool Builders: Outlet & Fixture Detailing

The Professional's Challenge

Sealing lights, drains and fittings in constantly wet, high-pressure environments.

The Adheseal Solution

Apply bead inside recess, install fixture or mortar to confine. Expansion maintains a tight seal even under pressure.

Best Practice Note

Do not overfill; use bead size that fits the recess so expansion is fully contained.