Polyurethane Crack Injection Kit 10-60ft

Polyurethane Foam Foundation Crack Injection Kit — 10ft to 60ft

Low-Pressure Polyurethane Injection That Stops Leaking Concrete Foundation Cracks From the Inside — No Excavation

Leaking poured concrete basement foundation cracks
Non-structural cracks: vertical or diagonal foundation cracks
Concrete pool cracks: vertical or diagonal pool cracks
Concrete ceilings: bunkers or any flat concrete roof
Pipe openings and holes: seal gaps around pipes and other openings
Leaking voids and wall spalls: fill voids and repair damaged concrete
Two foam options — 102 standard and 103 wide-crack / void-fill
Foam expands 20x on contact with water — permanent watertight seal
No excavation — repair from the inside
Free NextStar Technical Support — 1-866-445-3984
Ships USA & Canada

Why Choose NextStar Kits?

No Excavation Needed: repair leaks from the inside, no digging required.
Complete Kits: everything you need is included, from tools to materials.
Professional Results: contractor-quality repairs with ease.
Expert Support: backed by NextStar's technical support and guidance.

Crack Width Range — 1/32 to 3/8 Inch, Two Foam Options

This kit covers the full range of non-structural leaking cracks by offering two polyurethane foams. The standard 102 foam handles the common cracks; the 103 wide-crack foam is a dropdown option for wider cracks and voids. Both expand 20x on contact with water.

For cracks wider than 3/16 inch or for filling voids, select the 103 wide-crack polyurethane option at checkout. With enough product, 103 fills cracks up to 1/2 inch. For structural cracks (typically horizontal), polyurethane is not the right material — see the epoxy section below.

Kit Components — 10 ft Polyurethane Foam Base Kit

• Premium Polyurethane Foam #102: 1 dual cartridge (600ml) — seals up to 10 ft of crack, expands 20x to fill completely, creates a watertight flexible seal. Upgrade to 103 wide-crack foam at checkout for cracks over 3/16 inch or void fill.
• Crack Seal & Port Adhesive (903 Paste): 1 dual cartridge — secures injection ports and seals the crack surface. 903 Paste info
• Dual Cartridge Injection Gun: professional-grade tool for controlled polyurethane application
• Surface Injection Ports & Caps: 15 ports — enough for a 10 to 15 ft crack
• Static Mixing Nozzles: 2 nozzles (1/4 x 24) for proper two-part resin mixing
• Crack Injection Feed Hose: with shut-off valve for controlled application
• Mixing Tools: trowel, mixing sticks, water syringe
• Safety Gear: safety goggles and 4 pairs of nitrile gloves
• Wire Brush: for crack cleaning and surface prep
• Complete Instructions: step-by-step guide, instructional flash drive video, and MSDS safety data
• Ships to USA and Canada

Kit Sizes — 10ft, 20ft, 30ft, 40ft, and 60ft

All kits include the base tools: dual cartridge injection gun, wire brush, safety goggles, 4 pairs of nitrile gloves, trowel, mixing sticks, water syringe, and complete printed instructions with flash drive video. Quantities shown are totals for each kit size. The 103 wide-crack foam is available as a dropdown option on every size.

Video: Basement foundation crack repair using low-pressure polyurethane foam injection. Shows port placement every 8 to 10 inches, crack sealing with 903 paste, curing time, and step-by-step injection from the lowest port upward. Covers snap ties, spalls, pipe openings, and corner cracks. Applies to all kit sizes, 10ft through 60ft.

Easy to Use as a DIY Kit, or Upgrade to a Professional Tool — Same Products

NextStar polyurethane foam crack injection kits are a professional-grade solution against water leaks in concrete walls. The kit is user-friendly enough that someone with minimal DIY experience can use it — no construction expertise, no specialized equipment, no exterior digging or excavation. The low-pressure injection process fills cracks, pores, pipe openings, voids, and joints from the inside using an industry-approved method.

These kits contain the same product professional contractors use to repair leaking cracks. All repair essentials, including tools, are provided. You follow the manual and perform the repair without professional assistance, and the result is as secure as a contractor repair. Each kit includes a flash drive showing many real-world scenarios such as spalls, snap ties, and other common basement wall repairs.

When Is Polyurethane Foam Injection Recommended?

Polyurethane injection is the recommended solution for sealing and waterproofing non-structural cracks in poured concrete walls — leaking, wet, or damp cracks and flaws. These kits work very well for concrete cracks from 1/32 inch (1mm) to 3/8 inch, using 102 foam to 3/16 inch and the 103 wide-crack option above that.

Active leaking cracks. If a crack is ultra-fine, has been repaired before, or is not visible but will not stop leaking or weeping, the High-Pressure Polyurethane Kit may be the better choice — it works whether the wall is wet or dry.

Why Polyurethane Foam Crack Injection Works

Polyurethane foam is hydrophobic — it reacts with moisture and water. Unlike concrete, it does not absorb or retain water but expels it during the reaction. The foam creates a watertight seal through the full wall thickness by filling every corner and open space of the crack from the inside, leaving no room for water to penetrate, settle, or seep.

The high-density foam expands 20x its original volume and does not lose volume over time, so the seal is permanent. When cured it forms a semi-flexible resin that keeps its integrity over decades despite ground movement and seasonal temperature change.

Epoxy vs Polyurethane — Which Kit Should You Choose?

The two materials do different jobs. Polyurethane seals leaking non-structural cracks by expanding against moisture and staying flexible. Epoxy glues the wall back together as one solid piece for structural cracks. Use this polyurethane kit to stop water; use epoxy when the crack needs structural strength.

When a crack requires structural reinforcement, you need a material that adds strength to the wall. Polyurethane foam does not provide structural strength and is generally for non-structural cracks. For structural repairs, NextStar's Epoxy Foundation Crack Repair Kits are the right choice — epoxy injects with a similar low-pressure method but bonds the wall into one piece. If the wall is seasonally moving, reinforce the repaired cracks with carbon fiber after injection.

Structural Cracks Are Generally Horizontal

Wide horizontal or diagonal cracks can signal structural problems — contact a local structural engineer for recommendations. Most cracks in poured concrete foundations are already stable and are repaired simply to stop water. Basement wall cracks are commonly vertical or diagonal, and many begin at the corner of poured window cut-outs. For that type of leak, expanding polyurethane foam is the best repair: it stays flexible, allows for concrete's natural thermal movement, and expands 20x its volume on contact with water to fill the full crack depth so water will not find the crack again.

Tips & Notes for Repairing Leaky Foundation Walls and Cracks

1. Don't be in a rush — it can take up to 5 minutes for the polyurethane to travel to the next port.
2. Very small hairline cracks require heating the polyurethane cartridge in hot water in advance for better flow.
3. Above-grade cracks on the foundation exterior need sealing with epoxy paste, sealant, or hydraulic cement to keep product in the wall during curing.
4. Corner cracks: standard ports can be cut or bent to fit a corner crack, or add corner ports to your order.
5. Spring-Loaded Contractor Tool is recommended for 30 ft or more of repairs or ongoing large projects.
6. Dry concrete walls: the surface where you apply the sealing paste should be dry and clean during sealing — after that the wall can be wet. A wet wall prevents the port and crack sealer from sticking.

The Seven Steps to Low-Pressure Polyurethane Crack Injection

1. Clean the crack. Using the wire brush provided, vigorously clean the crack's full length to remove debris or loose paint so the surface is clean for port attachment.
2. Mix the port setting paste. Dispense a small amount of Type 903 paste onto cardboard or a paper plate and mix by hand until it turns grey.
3. Attach surface ports. Using the paste, attach surface ports to the wall every 8 to 10 inches apart along the crack.
4. Seal the crack surface. Mix more paste and seal between the ports and over the exposed crack to keep product in the wall during injection. Let the sealing paste cure until hard, approximately 1 to 2 hours.
5. Flush with water. Using the syringe provided or a water bottle, flush water into each port to confirm it is open, provide moisture for the polyurethane reaction, and verify the crack seal has no leaks.
6. Load the injection tool. Install a static mixing tube on the cartridge and load it into the dual dispensing tool. Attach the feed hose for hard-to-reach ports.
7. Inject from the bottom up. Start at the lowest port. Inject slowly until foam arrives at the next port above, cap that port, and move up. Repeat to the top port — the repair is now waterproof.