Jaclan Waterproof Plugging Mortar – Fast-Setting Water-Stop Cement for Active Leaks
 
Jaclan Waterproof Plugging Mortar is a rapid-setting, expanding water-stop cement designed to instantly seal active water leaks, seepage and running water in concrete and masonry.
 
When mixed with clean water, it forms a high-strength putty that expands as it cures, creating a permanent watertight seal even where water is under pressure. Once cured, the material develops similar strength and performance to concrete.
 
This professional-grade waterproof cementitious mortar is suitable for internal and external use – above or below ground – and is ideal for emergency leak repair, tanking work and structural waterproofing.
 
Advantages
 
Instantly stops running water and seepage in concrete & masonry
Expands during cure to form a permanent monolithic seal
Fast setting – initial set in approx. 60 seconds
Suitable for use above and below ground, internal & external
Can be applied to damp surfaces and active leaks
Suitable for basements, tanks, lift pits, sewer chambers & retaining walls
Non-flammable, non-metallic and chloride free
Cures to match concrete-like hardness and durability
 
Typical Applications
 
Plugging active water leaks in walls and floors
Sealing water ingress in basements and cellars
Waterproofing concrete tanks, sumps and manholes
Stopping joints that are leaking under hydrostatic pressure
Emergency water-stop repairs before tanking or coating
Repairing cracks, honeycombing and voids in masonry
 
Mixing & Application
 
Mix at approx. 4:1 powder to water ratio (≈1.25 L water per 5 kg)
Blend to a stiff, putty-like consistency
Work material by hand into leak point while still plastic
Initial expansion and set typically within 1–2 minutes
Protect until fully hardened (approx. 5 minutes)
Can be over-coated once fully cured
 
Property
      Value
Form
      Grey cementitious powder
Initial Set
      1–2 minutes
Full Cure
      Approx. 5 minutes
Application Temp
      +5 °C to +30 °C
Use
      Internal & external, above & below ground
 
Downloads
📄 Product Data Sheet – Full technical information & safety guidance
 
Why Choose Jaclan?
 
Jaclan Waterproof Plugging Mortar provides a true water-stop cement solution for dealing with live leaks where standard mortar cannot be applied. Its expanding action and rapid cure make it a trusted professional material for structural waterproofing and emergency leak control.
 
Frequently Asked Questions
 
Is Jaclan Plugging Mortar the same as water-stop cement?
Yes. It is a rapid-setting waterproof cement designed specifically for stopping active water leaks.
 
Can this mortar be used below ground?
Yes. Jaclan is suitable for internal and external use, above or below ground, even where water pressure is present.
 
How fast does water-stop cement set?
Jaclan begins to set in around 60 seconds and reaches full cure within approximately five minutes.
 
Can I use it on actively leaking concrete?
Yes. It is designed to plug live leaks and can be worked into joints, cracks and holes where water is flowing.
 
Does it expand while curing?
Yes. Jaclan expands as it sets, forming a monolithic watertight seal.