For active water leaks under pressure through holes, cracks, and openings in concrete and masonry, Gripset C-Plug forms an instant, non-shrink waterproof seal. This rapid-setting cementitious compound stops flowing water in underground car parks, basements, lift shafts, water tanks, and concrete pipes before curing to the mechanical strength of concrete.
C-Plug uses a rapid-setting, non-shrink chemical mechanism to expand slightly and lock into concrete or masonry cavities, blocking active water pressure. Hand-mixed and applied in small, individual batches, it goes from a paste to an initial set in under 60 seconds, allowing installers to hold back water flow manually until the seal is established. It does not contain additives that promote the corrosion of steel reinforcement, making it compatible with structural concrete repairs, subterranean joint filling, and the rapid anchoring of bolts, fixtures, and pipes.
Grind open cracks, joints, or holes to a minimum width and depth of 20mm. For high-volume leaks, increase the cut depth to a minimum of 40mm. Cut sides to a square or dovetail profile where possible, avoiding "V" profiles, smooth finishes, or feathered edges. Flush the area with clean water to remove loose debris, and ensure the substrate is thoroughly damp before application.
Mix by hand using a spatula or similar tool; do not use electric stirrers or paddle mixers. Limit batch sizes to a maximum of one handful (approximately 0.5kg of powder) per application, using approximately 150ml of clean 20°C water per 1kg of product. Once mixed to a putty consistency, press C-Plug firmly into the cavity using a gloved hand. Hold firm pressure until the initial set occurs (30 to 60 seconds), then slowly remove your hand. Keep the cured plug damp using a mist spray or damp sponge for 15 minutes after installation.
To establish long-term protection against future dampness and negative water seepage in subterranean structures, coat the cured C-Plug with Gripset C-1P flexible cementitious membrane. For active leaks at wall-to-floor junctions, cut out the joint to a minimum 20mm width, pack with C-Plug, and form a 45-degree, 40mm wide cove at the junction before over-coating with the membrane.
Gripset C-PLUG begins setting in 30–60 seconds, with a final set in 2–4 minutes. This rapid action is critical for stopping active water flow and working under pressure.
Yes, Gripset C-PLUG is specifically designed for active leak sealing, forming an instant waterproof barrier against hydrostatic pressure. Prepare the substrate with square or dovetail edges and dampen before application.
Yes, the formulation is non-toxic, non-staining, and odour-free. This makes it suitable for sealing leaks in potable water storage structures without contamination.
No, Gripset C-PLUG is formulated for concrete and masonry substrates only. For non-cementitious materials like metal, plastic, or timber, a different product is required.
Gripset C-PLUG must be hand mixed only to achieve the correct set times. Avoid using electric mixers or paddle stirrers, as these can accelerate the set beyond the working window.
| Application | Key benefit | Primary trades |
|---|---|---|
| Sealing active water leaks in concrete and masonry | Forms an instant, high-strength waterproof barrier against hydrostatic pressure in under 60 seconds. | Waterproofers, Builders, Civil Contractors |
| Leak repair in water tanks and retention structures | Non-toxic and non-staining formulation is safe for potable water storage applications. | Waterproofers, Civil Contractors |
| Stopping leaks in basements, cellars, and lift pits | Arrests water ingress quickly, preventing further structural damage in negative water pressure conditions. | Waterproofers, Builders |
| Repairing concrete pipes, culverts, and tunnels | Creates pressure-resistant seals, maintaining integrity in submerged and high-flow underground environments. | Civil Contractors, Plumbers |
| Forming fillets at wall/floor junctions in water-retaining structures | Creates durable, rigid coves that enhance the performance of subsequent waterproofing membranes. | Waterproofers, Builders |
| Anchoring bolts, fixtures, and conduits in damp concrete | Provides rapid, structural grip and secure embedment even on saturated substrates. | Builders, Plumbers, Electrical Contractors |
Remove loose material, laitance, de-bonded coatings, curing agents, release agents, waxes, oils/grease, moss and grime. Flush with clean water to remove fines and leave the substrate damp (no standing water).
Chase to a minimum 20 mm width and depth with square or dovetail edges. For high-volume leaks, increase depth to ≥40 mm. Avoid V-shaped profiles. Leave a rough mechanical key.
At wall/floor junctions, chase the joint to at least 20 mm and slightly back into the wall. After sealing, form a ~45° cove ~40 mm wide where required.
Mix by hand only to a stiff paste/putty. Prepare small batches you can place within ~1 minute.
As a guide, use ~150 mL of water per 1 kg of powder. Use mixing water at approximately 20 °C to enable correct strength development.
Limit each batch to about one handful (~0.5 kg). Place powder into a clean pail, add water, and mix quickly with a spatula until uniform. Hold the mix in a gloved hand until warmth or signs of initial set are felt.
Press the mixed compound firmly into the opening, maintaining constant hand pressure until initial set.
Seat the plug against the direction of water flow. Maintain pressure for ~30–60 seconds until the material locks. Remove your hand gradually.
For larger defects, place multiple small plugs, working outside-in until the area is fully sealed.
Once the plug has set, lightly re-dampen to support early hydration, then dress to profile.
After final set, mist or sponge with clean water for ~15 minutes.
When hardened, the plug can be sanded or ground to match existing structural contours.
For long-term dampness and seepage control (negative-side), integrate with the Gripset waterproofing system.
Once leaks are sealed and the plug has set, overcoat with Gripset C-1P flexible cementitious membrane according to membrane TDS guidance.
Form the 45° cove before membrane application to reduce stress concentration and improve waterproofing continuity.
Apply to damp (not flooded) cementitious substrates only. Avoid frozen surfaces and remove ice where freezing conditions exist.
Cold ambient conditions slow curing. Slightly warm mix water may help maintain set times. Store product off concrete floors and out of direct sun.
Do not use over non-cementitious surfaces or as a sealant/filler for expansion/movement joints.
Wear impervious gloves (e.g., nitrile), safety goggles or a face shield, and protective clothing to prevent skin or eye contact. Use a dust mask (P2/P3) during mixing to avoid inhaling cement dust.
Use in well-ventilated areas. Although non-toxic and odour-free, cement dust can be harmful if inhaled. Ensure adequate airflow, especially in enclosed spaces like basements or tunnels.
Store in sealed pails in a dry environment, protected from moisture ingress. Avoid direct sunlight or storage on bare concrete floors to prevent premature hardening. Dispose of waste according to local regulations.
Correct substrate preparation is crucial for Gripset C-PLUG to achieve maximum bond and immediate leak arrestment.
Surface prep: Remove all loose material, coatings, and contaminants. Chase cracks or holes to a minimum 20 mm width and depth, ensuring square or dovetail edges to create a mechanical key. Flush thoroughly with clean water to remove fines. Dampen the area before application, ensuring no standing water.
Primer: Not required. The product bonds directly to sound, pre-dampened concrete.
Surface prep: Chase leaking joints or cracks to at least 20 mm, squaring the sides where possible. Remove dust and contaminants, then flush and dampen. Maintain a rough profile for mechanical keying.
Primer: Not required. Pre-dampen porous masonry to prevent rapid water suction and ensure proper bond development.
Surface prep: Cut out the joint or crack to a minimum 20 mm width, chasing slightly into the wall for a secure fit. Clean thoroughly, flush to remove dust, and dampen. After plugging, a ~45° cove approximately 40 mm wide can be formed for water-retaining structures.
Primer: Not required. For long-term waterproofing, overcoat with Gripset C-1P flexible cementitious membrane once the plug has set and cured.
Surface prep: Grind or chase leaking joints or holes to at least 20 mm; for high-volume leaks, increase to ≥40 mm. Clean, flush, and dampen before placement. For larger areas with active flow, work from the outside toward the centre.
Primer: Not required. Once sealed and set, the product can be sanded or ground to match existing contours.
Surface prep: Remove any release agents, curing compounds, coatings, or primers that could inhibit bond. Mechanically roughen the surface to expose sound concrete, flush thoroughly, then dampen before application. Bond relies on a clean, roughened, pre-dampened surface.
Primer: Not required. Do not apply over incompatible or delaminating coatings.
| Property | Value |
|---|---|
| Appearance | Grey powder |
| Density | 2150 kg/m³ |
| Tensile Strength | 3.0 N/2 mm |
| Compressive Strength | 35 MPa |
| Trafficable Time | 2–4 minutes |
| Optimal Application Temperature | Approximately 20°C |
| Mixing Ratio (Water:Powder) | 150 mL per 1 kg |
| Packaging | 4 kg and 15 kg bags (in pails) |
| Shelf Life | 12 months (dry storage) |
Here are some common examples on where Gripset C-Plug used by our customers.
