Water leaks don't wait for dry conditions. When water is actively pouring in, you need an immediate, definitive stop. Lamposilex delivers that critical relief, sealing leaks even under pressure, preventing further damage and structural issues instantly.

Why this product exists

Lamposilex is an ultra-fast setting hydraulic binder specifically engineered by MAPEI Research Laboratories to confront active water ingress. Unlike conventional mortars that demand dry conditions and extended curing, this specialised formulation sets directly into active leaks, even when under pressure.

Its chloride-free composition ensures substrate compatibility, while its plastic-thixotropic consistency allows vertical application without formwork. It owns the job of emergency sealing in critical environments like basements, subways, tanks, and structural joints.

The numbers that matter

With a pot life of approximately 1.5 minutes at +20°C, Lamposilex demands precise, rapid application. This ultra-fast setting ensures immediate leak control, even under active water pressure, requiring installers to mix only what can be applied instantly.

After only half an hour, it achieves 17 N/mm² compressive strength. This rapid strength development secures the repair against ongoing water force and allows subsequent work to proceed without extended delays. Its formulation is also certified to AS/NZS 4020:2018 for potable water contact, ensuring suitability for critical infrastructure like drinking water tanks and reservoirs.

What it's like to use

Lamposilex requires quick action due to its rapid setting. Mix 1kg of powder with 280g of water, stirring manually with a trowel to achieve a smooth, lump-free paste. For stopping active leaks, mould the mix into a 'cork' shape, wait a few seconds for it to begin curing, then force it into the crack or hole. Maintain pressure for 2-3 minutes until fully set.

When sealing rigid joints, work the mix into the cavity immediately after preparation using a trowel or float. Keep the surface damp for the initial 15-20 minutes to aid optimal cure. For warm conditions, use very cold water for mixing and keep the material out of direct sunlight. In low temperatures, use water around +20°C and store the product in heated rooms to prevent delayed setting. Tools can be cleaned with water before the product hardens.

Where this product excels

• Active Leak Stopping: Immediately seals water leaks in basements, subways, and other below-grade structures, even when water is actively under pressure.
• Tank Repair: Provides waterproof sealing for leaks in above-ground tanks, including those holding potable water, thanks to its AS/NZS 4020:2018 compliance.
• Structural Joint Sealing: Effectively waterproofs rigid joints between walls and floor slabs, preventing water ingress in critical structural areas.

Choose this when

• You need to immediately stop active water leaks, even under pressure.
• The application demands rapid setting and high early strength to resist water force.
• The repair is within potable water infrastructure or requires AS/NZS 4020:2018 compliance.
• You are sealing rigid joints or cracks in concrete, masonry, or mineral substrates.

Don't use this when

• Not for: Applications needing extended workability or a longer pot life due to its rapid 1.5-minute set time.
• Not for: Mixing with other binders such as lime, cement, or gypsum.
• Not for: General purpose patching or crack repair where slow curing is acceptable. For slower-setting repairs, consider mapegrout-t40 or mapegrout-fast-set-rapido.
• Not for: Concrete surface finishing where a fine texture is required. For such applications, planitop-fine-finish is more suitable.