Sika Injection 101
One-Component Hydrophilic Polyurethane Injection Resin for Stopping Active Water Leaks in Concrete
Authorized Project Distributor — Sika India | Space Arc Engineering, Ghaziabad
Product Overview
Sika Injection 101 is a one-component, low-viscosity, hydrophilic polyurethane prepolymer from Sika that requires water as its curing agent — the resin reacts with water present in the crack or void to rapidly expand and form a closed-cell polyurethane foam or flexible gel depending on the water-to-resin contact ratio. This water-reactive expansion mechanism makes Sika Injection 101 uniquely suited for emergency repair of active leaks and flowing water ingress in concrete structures where conventional cementitious or epoxy repair products would be washed out before they could set. On contact with water in a wet or actively leaking crack, Sika Injection 101 expands up to 10 to 20 times its original volume, filling the crack void and surrounding pore network with polyurethane foam that physically blocks the water flow. The foam is flexible and slightly elastic, accommodating minor crack movement without losing the water seal — this flexibility distinguishes it from rigid epoxy crack injection (Sikadur series) which is appropriate for structural cracks requiring rigid consolidation but not for active water-filled cracks with movement. Sika Injection 101 is injected using single-component injection pump equipment through pre-installed injection ports (packers) drilled and epoxy-fixed in the concrete adjacent to the crack or construction joint at 150 to 300 mm centres. The low initial viscosity (around 150 to 300 mPas) allows penetration into fine cracks before the water-reactive expansion begins. For basement walls and slabs with active groundwater leakage through construction joints, honeycombed concrete, or cracks with water flow, Sika Injection 101 provides immediate water stopping that can then be followed by longer-term surface repair. Space Arc Engineering supplies Sika Injection 101 for emergency leak repair and basement remediation projects across Delhi NCR, Ghaziabad, Noida, and Northern India.
Applications
- Active leaking construction joints in basement walls and slabs — emergency water stopping
- Flowing cracks in concrete retaining walls under groundwater pressure
- Honeycombed concrete sections with active water ingress in underground structures
- Tunnel lining concrete construction joint and crack injection
- Underground water tank wall repair — stopping active seepage through concrete cracks
- Pre-injection of Sika Injectable Hose (SIH) at completed construction joints before water ingress begins
Key Advantages
- Water-activated — requires moisture to cure, ideal for wet and actively leaking cracks
- Rapid expansion (up to 10 to 20 times volume) — fills crack network quickly
- Flexible foam or gel — accommodates minor crack movement without losing seal
- One-component — simple single pump injection, no mixing required
- Low initial viscosity — penetrates fine cracks before expansion begins
- Immediate water stopping — visual water flow stops during injection in most cases
Technical Data
| Type | One-component hydrophilic polyurethane injection resin |
| Viscosity | 150 to 300 mPas (initial, before water contact) |
| Expansion Ratio | Up to 10 to 20 times volume on contact with water |
| Cured Material | Flexible closed-cell polyurethane foam or gel (water content dependent) |
| Injection Equipment | Single-component low-pressure injection pump and packers |
| Pack Sizes | 1 litre, 5 litre containers |
Get a Quote
+91 9999155255 | info@space-arc.com | Space Arc Engineering, Sahibabad, Ghaziabad
Frequently Asked Questions
What is the correct packer spacing and drilling angle for injecting Sika Injection 101 into an actively leaking vertical construction joint in a 250 mm thick basement wall?
For Sika Injection 101 injection into a vertical construction joint in a 250 mm basement wall with active water ingress, the packer drilling and spacing procedure is as follows. Packer spacing: drill injection packers at 150 to 200 mm vertical centres along the leaking joint. At this spacing, the resin from adjacent packers will overlap in the joint cavity and ensure complete filling of the joint width. Drilling angle: drill each packer hole at 45 degrees to the wall face, angled so the drill bit intersects the joint plane at mid-depth (approximately 125 mm from the face for a 250 mm wall). If drilling at 45 degrees, the drill hole length to reach the joint centre in a 250 mm wall is approximately 125 mm / cos(45 degrees) = approximately 175 mm. The 45-degree drilling angle ensures the packer hits the joint at the structural mid-point and provides a longer resin travel path from the injection point to the joint, improving filling coverage per packer. Packer installation: blow clean the drilled holes with compressed air. Install 12 mm diameter expandable mechanical packers (or epoxy-fixed port packers), torqued to the concrete to form a sealed connection. Injection sequence: begin injection from the lowest packer and work upward for a vertical joint, or from one end to the other for a horizontal joint. Inject at low pressure (2 to 5 bar) until resin begins to emerge from the adjacent packer, then move to the next packer upward. After injection, leave the packers in place for 24 hours then remove and patch the packer holes with rapid-setting mortar.
After stopping an active leak with Sika Injection 101, what additional repair and waterproofing steps are required to ensure long-term waterproofing of the joint?
Sika Injection 101 polyurethane foam injection is an emergency water-stopping measure that halts immediate water ingress but is NOT a long-term structural waterproofing solution on its own. The polyurethane foam can degrade over time under sustained hydrostatic pressure, and the foam does not provide structural consolidation or a durable chemical-resistant barrier for long-term service. The following additional steps are required after water-stopping injection for long-term waterproofing. Step 1 — Surface preparation: after the injection foam has cured (minimum 6 to 8 hours), remove all loose, damaged, and contaminant-affected concrete at the construction joint face using chipping hammer or grinding to expose clean, sound concrete. Cut a chase (groove) along the full joint length approximately 20 mm wide x 25 mm deep to provide a sealant bed. Step 2 — Chase filling: fill the cleaned chase with SikaFlex Pro or Sikadur 31 CF Normal depending on whether movement is expected at the joint. Step 3 — Crystalline waterproofing coat: apply two coats of SikaTop 107 Seal crystalline waterproofing coating (brush-applied) over the full repaired joint area — minimum 500 mm width centred on the joint — to provide long-term crystalline sealing of the concrete permeability adjacent to the joint. Step 4 — Protective render: apply SikaTop 122 Plus or Sika Monotop 612 polymer repair mortar over the crystalline coat once it has cured (minimum 24 hours) to protect the waterproofing treatment from mechanical damage.
Can Sika Injection 101 be used in a dry crack with no active water flow, and will it still expand and seal the crack?
No — Sika Injection 101 is a hydrophilic (water-activated) polyurethane injection resin that requires the presence of water to initiate and sustain the curing and expansion reaction. In a completely dry crack with no moisture present, Sika Injection 101 will have extremely slow and incomplete reaction — the resin will remain in a liquid or semi-liquid state in the crack and will not expand to fill the crack void. For dry cracks (no moisture, no water flow, crack is open-air dry), the correct injection resin is a low-viscosity epoxy injection resin such as Sikadur 52 (a two-component, low-viscosity liquid epoxy injection resin). Sikadur 52 cures through a chemically activated epoxy-amine reaction that does not require water — it flows into and fills dry cracks and cures to a rigid, high-strength epoxy consolidation that restores structural continuity across the crack. For cracks that are slightly damp or show periodic moisture (wet during rainy season, dry during summer): these cracks can be treated with Sika Injection 101 if water is first introduced into the crack by water injection through the packer ports to initiate the reaction, or specified as Sika Injection 201 (hydrophobic polyurethane injection resin) which cures as a flexible elastic seal without requiring water as a co-reactant. Contact Space Arc Engineering technical team to determine the correct injection resin for the specific crack condition on your project.
Source Sika Injection 101 for Your Project
Space Arc Engineering is an Authorized Project Distributor for Sika India serving Delhi NCR, Ghaziabad, Noida and Uttar Pradesh.
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