Mapeproof Swell is a cartridge-applied hydrophilic sealant paste that expands when exposed to water. Unlike an ordinary exposed silicone joint sealant, it is intended to form a water-reactive seal within suitably confined concrete construction joints and other approved details.
For water-tight concrete construction
Where a new concrete pour meets an earlier pour, the construction joint can form a potential water path. A correctly positioned continuous bead of Mapeproof Swell helps resist that path when water reaches the material and triggers its expansion. The paste format is particularly useful for forming a continuous seal along irregular joint details and approved penetrations.
Select by the joint design
Mapeproof Swell is suited to specified concealed, confined hydrophilic sealing details in structures such as basements and tanks. It is not a general bathroom silicone or exposed expansion-joint sealant. Performance depends on correct bead position, concrete cover and the design of the complete water-resisting system.
Before you start
Ensure the substrate, joint dimensions and confinement meet the project requirements. Avoid premature exposure before the concrete detail is completed; follow the approved application and curing procedures.
How much does Mapeproof Swell expand?
The current MAPEI data states a minimum 100% volumetric expansion in water.
How quickly does it skin?
About 180–200 minutes.
What is the polymerisation rate?
About 2mm every 9 hours.
Does the bead need to be confined?
Yes. The hydro-expansive seal relies on proper confinement within the joint or penetration detail.
- Concrete.
- Reinforced-concrete construction joints.
- Pipe penetrations and sleeves.
- Concrete cracks, formwork spacers and service outlets where the sealant can be confined.
Mapei Mapeproof Swell Sealant Physical Properties
| Property | Value |
|---|---|
| Material Type | Hydro-expansive, rubber-based hydrophilic sealant paste |
| Chemical Composition | Insoluble in water (hydrophilic) |
| Colour | Light grey |
| Density | 1250–1300 kg/m³ |
| Viscosity | 700,000 mPa·s (Rotor F, 5 RPM) |
| Solids Content | 90 % |
| Tensile Strength | 2.5 N/mm² |
| Shore Hardness | 32 |
| Swelling | ≥ 100 % |
| Skin Time | 180–200 min |
| Cure Rate | 2 mm per 9 h |
| Coverage Rate | ≈ 320 ml per 3 m (for 6-13mm bead) |
| Maximum Gap Fill | 6–13 mm |
| Water Pressure Resistance | 1 atm (when confined) |
| Packaging | 320 ml cartridge, Box of 6 (320 ml each) |
| Shelf Life | 12 months |
| Storage Conditions | Dry place at 15 °C to 25 °C |