Carbon Fiber Stitch & Epoxy Ultimate Foundation Crack Repair Kit — Seal and Lock in One Complete System
Epoxy Injection Repairs the Crack. Carbon Fiber Stitches Stop It From Ever Re-Opening.
Epoxy injection — 12,000 PSI compressive strength, bonds concrete back to original integrity
Pre-tensioned carbon fiber stitches — lock the crack against re-opening under tensile load
Addresses both failure modes — epoxy handles compression, stitches handle tension
Covers up to 15 ft of foundation wall crack
1,800 ml of MV injection epoxy — for structural cracks 1/8 to 1/4 inch wide
10 pre-tensioned carbon fiber stitches — 44 sq.cm bonding area, larger than any competitor
Countersunk flush finish — paintable after cure
No exterior digging — complete inside-wall repair
ASTM certified — C-882, D-638, D-695, D-732, D-648
10-Year Limited Warranty on carbon fiber stitches
Free NextStar Technical Support — 1-866-445-3984
Ships USA & Canada
Why This Kit Exists — The Right Solution for Most Structural Foundation Cracks
The most common structural crack in a poured concrete foundation is one you've probably seen — a vertical or diagonal crack running down from a window corner, a cold joint, or a wall section under concentrated load. These cracks are stable but have opened under tension and won't stay closed with epoxy alone over the long term.
This kit was designed specifically for that situation. It gives you a complete structural repair in one purchase — no need to separately select compatible epoxy, stitches, and tools, and no risk of buying products that don't work together. If you've had a crack injected before and it came back, stitching is what was missing from the first repair.
When this kit is the right choice:
- Vertical or diagonal cracks in poured concrete walls, especially those originating from window corners
- Cracks that are stable but have opened under tension or freeze-thaw cycling
- When you want a long-term economical solution that goes beyond epoxy alone
- When full-length carbon fiber wall straps feel like overkill for a localized crack
Why epoxy injection alone isn't always enough
Epoxy addresses compression failure — it flows into the crack and bonds the two faces together at 12,000 PSI. For a crack that has completely stopped moving, epoxy alone is a valid repair. But the same forces that opened the crack — hydrostatic soil pressure, freeze-thaw cycling, foundation settlement — continue to apply tensile force across it after the repair. Epoxy has excellent compressive strength but limited tensile resistance on its own, which is why a repaired crack can reopen along the same line or just beside it.
Why stitches alone aren't enough either
Carbon fiber stitches resist tensile force — they span the crack perpendicular to it and are pre-tensioned so they begin resisting load immediately with zero initial stretch. But stitches don't seal or structurally bond the crack faces together. Without epoxy filling the void, the crack remains open to water, continues to allow micro-movement between the faces, and the stitches carry all the load with no support from the wall itself.
Used together — one complete repair
The epoxy seals and bonds the crack in compression. The stitches lock it against reopening under tension. This combination is the same method used by professional waterproofing and structural contractors, now available as a single kit with everything matched and included.
Kit Components — Carbon Fiber Stitch & Epoxy Ultimate Kit
Epoxy Injection Components
3 Dual Cartridges MV Injection Epoxy — 1,800 ml total (600 ml each):
Medium Viscosity 121 MV epoxy for structural cracks 1/8 to 1/4 inch wide. 12,000 PSI compressive strength (ASTM D-695). Cures to 32°F (0°C). Gel time 20 minutes. Each 600 ml NextStar cartridge contains more than twice the material of competitor 185–250 ml caulking tubes — you will not run short before the crack is fully filled.
1 Dual Tube of Port Setting and Crack Seal Paste (Type 903):
Fast-setting two-part paste for attaching surface injection ports to the wall and sealing the crack surface between ports.
15 Surface Injection Ports with Caps:
Attach to the wall at 8–10 inch intervals along the crack. Extra injection epoxy cartridges available at checkout if your crack requires additional volume.
Epoxy Dispensing Tool with Feed Hose & Wire Brush:
Standard 18:1 ratio dual dispensing tool with shut-off feed hose for controlled low-pressure injection. Upgrade to the spring-loaded contractor tool at checkout for reduced hand fatigue on longer repairs.
Static Mixing Nozzles:
1/4 × 32 element static mixers for thorough two-component blending at the nozzle.
Carbon Fiber Stitch Components
10 Pre-Tensioned Carbon Fiber Stitches:
Pre-impregnated, unidirectional, pre-tensioned carbon fiber at 2,884 MPa tensile strength. 44 sq.cm bonding area — larger than Rhino (30 sq.cm), Fortress Staple (16.8 sq.cm), and Fortress Grid Stitch (9.5 sq.cm). Pre-tensioning means zero initial stretch before load resistance begins. Will not corrode. 10-Year Limited Warranty.
1 Set of Carbon Fiber Stitch Bonding Epoxy — 450 ml (A+B):
Dedicated epoxy for embedding and bonding the stitches in their slots. Gels in 1 hour, fully cures in 24 hours.
4.5 Inch Turbo Diamond Blade:
For cutting the 12 inch long installation slot perpendicular to the crack at each stitch location. Requires a 4.5 inch hand grinder (not included).
Accessories and Safety Gear
Safety Goggles and 4 Pairs of Nitrile Gloves
Trowel and Putty Knife
Flash Drive Instructional Video & Written Instructions
MSDS Safety Data
Additional epoxy cartridges are available at checkout if your crack width requires more volume. Use the calculator below to estimate your needs before ordering. Call 1-866-445-3984 with any questions.
Epoxy Volume Calculator — How Much Do You Need?
The kit includes 1,800 ml of MV injection epoxy. Use this table to estimate whether the base kit is sufficient for your crack, or whether additional cartridges are needed at checkout.
| Crack Width |
Epoxy Volume per Foot (10 in. thick wall) |
Kit Coverage (1,800 ml) |
| 1/8 inch |
240 ml per ft |
~7.5 ft |
| 1/4 inch |
480 ml per ft |
~3.75 ft |
For cracks longer than these estimates, add extra cartridges at checkout — 1, 2, 3, or 4 additional 600 ml tubes are available. For cracks under 1/8 inch, the kit will cover more footage. Use the online volume calculator for a precise estimate, or call 1-866-445-3984.
Installation — Two-Phase Process
This kit is a two-phase repair. Complete the epoxy injection first and allow it to fully cure before installing the carbon fiber stitches. The stitches are installed after the epoxy has bonded the crack — they lock the repair permanently against any future tensile movement.
Phase 1 — Epoxy Crack Injection (Day 1)
- Put on protective gear. Safety goggles and nitrile gloves before handling any materials.
- Clean the crack. Wire brush the full crack length to bare concrete, removing paint, efflorescence, and loose material.
- Mix the port setting paste. Dispense a small amount of Type 903 paste and mix by hand until grey and uniform.
- Attach surface ports. Using the mixed paste, attach surface ports every 8–10 inches along the crack.
- Seal the crack surface. Apply more paste between ports over the exposed crack. Allow to cure until hard — approximately 1–2 hours. Surface must be dry for best adhesion.
- Warm cartridges if needed. For tight cracks or cold conditions, warm epoxy cartridges in hot water for 5–10 minutes to improve flow.
- Load the injection tool. Install a static mixing nozzle and load the cartridge into the dispensing tool. Attach the feed hose. Purge a small amount onto cardboard to confirm both components are flowing evenly.
- Inject from the bottom up. Start at the lowest port. Inject slowly — epoxy can take up to 5 minutes to reach the next port. When epoxy arrives at the port above, cap the lower port and move up. Repeat to the top.
- Allow full cure. MV epoxy gels in 20 minutes and fully cures within 24 hours at 32°F or above. Do not install stitches until fully cured.
Phase 2 — Carbon Fiber Stitch Installation (Day 2)
- Plan stitch locations. Mark stitch locations every 9–18 inches along the crack, perpendicular to it. Closer spacing provides greater resistance. For a 15 ft crack at 12 inch spacing, 10 stitches covers the full length with one stitch remaining as a spare.
- Cut the slot. Using a 4.5 inch hand grinder with the included turbo diamond blade, cut a slot 12 inches long, ¾ to 1 inch wide, and 1.5 inches deep at each stitch location — perpendicular to and straddling the crack.
- Vacuum the slot. Remove all dust with a shop vacuum or compressed air. Dust prevents epoxy bonding.
- Mix the stitch epoxy. Mix the two-part carbon fiber stitch bonding epoxy by hand until uniform.
- Butter the stitch. Apply a coat of mixed epoxy to the carbon fiber stitch.
- Fill the slot. Trowel stitch epoxy into the slot to fill it approximately halfway.
- Install and finish. Press the epoxy-coated stitch firmly into the slot. Trowel additional epoxy over the top to fully embed the stitch flush with the surrounding concrete surface.
- Allow to cure. Stitch epoxy gels in 1 hour and fully cures in 24 hours. The surface can be painted or coated after full cure.
Tips & Notes
1. Always complete the epoxy injection first and allow full 24-hour cure before cutting stitch slots. Cutting slots while the epoxy is still curing can introduce micro-movement that disrupts the bond.
2. Stitch spacing. For cracks with active seasonal movement or extensive cracking, use 9 inch spacing rather than 18 inch. Tighter spacing adds reinforcement.
3. Stitch orientation. Always cut slots perpendicular to the crack — never parallel. Stitches only resist movement in the direction they cross.
4. For corner cracks, add corner injection ports to your order at checkout — standard ports can also be cut or bent to fit.
5. Not sure how much epoxy you need? Use the volume calculator or call 1-866-445-3984 before ordering.
6. Want the standalone kits instead? The Epoxy Injection Kit upgrades to 60 ft coverage. The Carbon Fiber Stitch Kit is available with 15 or 50 stitches.
Common Questions About the Stitch & Epoxy Combo Kit
Why use both epoxy injection and carbon fiber stitches — isn't epoxy enough?
Epoxy injection bonds the crack faces together at 12,000 PSI and restores the wall to its original structural integrity. But epoxy on its own has limited tensile resistance. The same forces that created the crack — hydrostatic soil pressure, freeze-thaw cycling, and foundation settlement — continue to apply tensile stress across the repair. Carbon fiber stitches are pre-tensioned and span the crack perpendicular to the direction of movement, resisting the tensile load that would otherwise re-open the repair over time. Together they address both failure modes completely.
Do I inject the epoxy first or install the stitches first?
Always inject the epoxy first and allow it to fully cure for 24 hours before cutting stitch slots. The epoxy seals and bonds the crack in compression — the stitches are then installed across the cured repair to lock it against tensile re-opening. Cutting slots into wet or partially cured epoxy can introduce movement that disrupts the bond.
What crack width is this kit designed for?
The kit includes Medium Viscosity (MV) epoxy formulated for structural cracks from 1/8 to 1/4 inch wide. For hairline cracks under 1/8 inch, Low Viscosity (LV) epoxy provides better penetration — call us to confirm the right viscosity for your crack. The kit asks you to specify crack width at checkout so we can include the appropriate epoxy viscosity.
How much epoxy will I need — does the kit include enough?
The kit includes 1,800 ml of injection epoxy. A 1/8 inch wide crack in a 10 inch thick wall uses approximately 240 ml per foot — enough for about 7.5 ft. A 1/4 inch wide crack uses approximately 480 ml per foot — enough for about 3.75 ft. For longer cracks, add extra 600 ml cartridges at checkout. Use the volume calculator for a precise estimate.
How far apart should the stitches be spaced?
Install stitches 9 to 18 inches apart depending on the degree of reinforcement required. For a 15 ft crack at 12 inch spacing, the 10 stitches in this kit cover the full length with one spare. For extensive cracking, active seasonal movement, or weaker concrete, use 9 inch spacing — add extra stitches at checkout if needed.
Will the carbon fiber stitches corrode over time?
No. Carbon fiber does not corrode, rust, or degrade. Steel staples begin corroding almost immediately after installation as moisture penetrates the cement used to fill the slot. The carbon fiber stitches in this kit are covered by a 10-Year Limited Warranty against failure under tensile load when installed per the instructions.
What is the difference between this kit and the standalone epoxy kit?
The standalone epoxy kit repairs the crack structurally and is the right solution for cracks that have stabilized and are no longer moving. This combo kit adds carbon fiber stitches for cracks that are subject to ongoing tensile stress — active seasonal movement, significant soil pressure, or any situation where the crack might re-open after injection. If in doubt, the combo kit is the more complete and permanent solution.
What ASTM standards does the epoxy meet?
NextStar's 121 MV epoxy meets: Tensile Strength 8,500 PSI (ASTM D-638), Compressive Strength 12,000 PSI (ASTM D-695), Shear Strength 5,100 PSI (ASTM D-732), Bond Strength 2,800 PSI (ASTM C-882), Deflection Temp 126°F at 264 PSI (ASTM D-648). The carbon fiber stitches meet ASTM C882, D648, D638, and D792.
Is technical support available if I have a problem?
Yes. Call NextStar toll-free at 1-866-445-3984 Monday to Friday 8:30 am to 5:00 pm. The flash drive included with the kit also contains real-world repair video examples covering voids, honeycomb, snap ties, and common wall scenarios.
10-Year Limited Warranty on carbon fiber stitches. Questions during your repair? Call our free technical support line at 1-866-445-3984.
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