Sunken driveways, tripping sidewalks, tilted patios, and settled garage slabs — lifted back to level with high-density polyurethane foam or traditional mudjacking. Cures in 15 minutes. Drive on it the same day.
A licensed local crew — usually out in 24 to 72 hours. Written scope, fixed price, no pressure.
Last February I got called out to a 2006 two-story on Trinity Church Rd on the Rowan County side of Kannapolis — one of the newer builder subdivisions that went up during the wave of construction after the N.C. Research Campus was announced. The homeowner's driveway had settled about two inches at the corner nearest the garage door, and the front stoop had pulled away from the house by nearly an inch, leaving a gap you could stick two fingers into. Water had been running down that gap and into the crawlspace at the corner of the foundation every time it rained, and the crawl was showing efflorescence on the block wall on that side. Classic Piedmont red-clay-plus-poor-original-compaction failure — the fill under the driveway apron had never been properly compacted when the house was built, and 15 years of wet-dry cycles had let it settle.
Concrete lifting with polyurethane foam is the fix for exterior slab settlement on the newer Kannapolis subdivisions. HMI TerraThane 24024 is the material we spec — a two-part expanding foam that gets injected through 5/8-inch holes drilled through the slab at a defined pattern, expands to fill any voids under the slab, and lifts the concrete back to grade in a controlled way. Cures to structural strength in about 15 minutes. The 5/8-inch holes get patched with color-matched grout after the lift. Whole process on a typical driveway apron and front stoop combo takes half a day with a two-person crew. Compared to mudjacking (the older cement-slurry method), poly is lighter, does not add load to the soil that is already failing, cures faster, and does not require the larger holes mudjacking needs.
On the older Cannon Mills housing in the West and East Kannapolis mill villages, exterior concrete lifting is a smaller part of the scope because most of the original Cannon houses do not have concrete driveways — they were built with grass or gravel driveways from the 1930s and the concrete additions came later, if at all. The concrete work we do on the mill houses is usually front walk lifting where a 1950s or 60s poured walk has settled toward the house and started dumping water at the foundation, or back stoop lifting on the concrete slabs that were added when kitchens were expanded in the 1970s. Village Park and Forest Park subdivisions on the north side of the city are our regular concrete lifting territory — driveways, front stoops, back patios, pool decks in a few cases. Free on-site inspection anywhere in Kannapolis, Concord, China Grove, Landis, and the surrounding Cabarrus and southern Rowan area.
Poly lifting on a Kannapolis subdivision driveway starts with mapping the settlement. I walk the slab with a 4-foot level and a string line, mark the low points, and probe the joints for any hollow-sounding sections that indicate voids underneath. On a typical driveway apron in Village Park or Forest Park the settlement is concentrated at the joint nearest the garage or at the corner where the driveway meets the front walk — those are the transition points where fill compaction is weakest. I photograph the elevation of the slab at multiple points, then plan the injection pattern based on the extent of the void and the target lift.
Injection hole pattern for HMI TerraThane on a 20-foot by 12-foot driveway apron is typically 5/8-inch holes on a 4-by-4-foot grid, drilled through the slab with a hammer drill. The two-part foam is mixed in the gun and injected through each hole in metered shots, starting at the low end and working toward the high end. The foam expands to about 25 times its liquid volume and cures in 15 minutes to structural strength. We monitor the slab elevation continuously during injection with a laser level so we can stop when the target lift is reached. Overlifting is worse than underlifting — the foam does not compress back down once cured — so precision matters.
Front stoop and porch slab lifting on the Cannon Mills mill houses in West and East Kannapolis is a similar process but with tighter pattern spacing because the slabs are smaller (typically 4-by-6 or 5-by-8 for a front stoop) and the settlement is often more concentrated. Cabarrus County and Rowan County do not require permits for concrete lifting itself — it is a maintenance repair, not a new structural element — so the paperwork is minimal. If the lift is being done in conjunction with foundation drainage work or interior perimeter drain installation, those may have their own permit requirements which we handle.
Post-lift, the 5/8-inch injection holes get patched with a color-matched cementitious grout. The slab is walkable immediately (the foam is at structural strength within 15 minutes) and drivable in about an hour. On driveway aprons we recommend the homeowner watch the joint at the garage door for the next season — if the underlying soil is still moving because of ongoing drainage issues, we will see it and can plan a second lift or address the drainage source (typically a downspout dumping right against the foundation apron). Trinity Church Rd and the newer subdivisions on the Rowan side sometimes have grading issues that need to be addressed at the same time — regrading the swale between houses or extending a downspout, which is not our lane but we will tell you on the inspection.
HMI TerraThane 24024 is our default polyurethane injection material for exterior slab lifting on the Kannapolis subdivisions. Two-part, closed-cell, expands to roughly 25 times liquid volume, cures to about 60 PSI compressive strength within 15 minutes. Density is about 4 pounds per cubic foot cured — lighter than the soil it displaces, so it does not add settlement-inducing load to fill that is already failing. Injection is through 5/8-inch holes drilled with a hammer drill on a 4-by-4-foot pattern for a standard driveway, tighter (3-by-3) for a small stoop or walk section where the void is more concentrated.
For interior slab lift on the partial-crawl-partial-slab houses that show up occasionally in the newer subdivisions (some builders on the Kannapolis Pkwy corridor put a slab section under the garage or utility room with a crawl under the rest of the house), we use the same HMI TerraThane material with tighter injection pattern control because the interior lift usually needs to bring a settled slab back into contact with the adjacent framing at a specific elevation. Laser level runs continuously during interior injection.
Grout for hole patching is a color-matched cementitious grout — SikaFlex-1a is not the right product for driveway hole patching because it is a polyurethane sealant not a cementitious grout. For any joint sealing between slabs after the lift is complete, SikaFlex-1a or a comparable polyurethane sealant is what we use. Concrete slab lifting equipment is a standard hammer drill for hole prep, a two-part injection gun rated for the TerraThane material, and a laser level for elevation control. Nothing exotic. What matters is the pattern, the metered shot volumes, and knowing when to stop injecting — overlift is not reversible.
Yes — Kannapolis is a regular concrete lifting route. Free on-site inspection anywhere in Kannapolis, fixed written quote before we touch anything.
Concrete lifting in Kannapolis skews heavily toward the 2000s Village Park, Forest Park, and Trinity Church Rd subdivisions where builder-era poorly compacted fill has settled 15 to 20 years in — the 1930s Cannon Mills mill village housing rarely needs it because most of those houses were built with grass or gravel driveways and the concrete additions came later.
28081, 28083. All Cabarrus & Rowan Counties addresses covered.
Mudjacking uses a cement and sand slurry pumped under the slab through 1.5 to 2-inch holes. It works but the slurry is heavy — about 100 pounds per cubic foot — which means it adds load to soil that just failed once already. Poly is 4 pounds per cubic foot cured, so it lifts without adding weight. Poly also cures in 15 minutes versus a day or more for mudjacking slurry, and the injection holes are 5/8-inch versus 1.5 to 2 inches so the patch is nearly invisible. On a driveway apron in Village Park or Forest Park where the underlying fill is likely to keep moving seasonally, poly is the durable answer. Mudjacking still has a place on very large slabs where cost per square foot matters and future settlement is not a concern. On residential in Kannapolis we spec poly.
It fixes the acute problem, which is water sheeting into the crawl at the settled corner. It does not fix the underlying reason the fill settled in the first place, which is almost always inadequate original compaction combined with a downspout or gutter dumping right against the foundation. So the order of operations matters: we lift the slab back to grade, which stops the acute intake, but we also want to look at the gutter and downspout situation. If the downspout at that corner is discharging within 3 feet of the foundation, an inexpensive downspout extension solves the future risk. If the grading itself is negative (soil sloping toward the house), that is a grading job outside our lane and we will refer. The lift plus the drainage fix together is what makes the repair last.
No, not for the lifting itself. Both counties treat polyurethane slab lifting as maintenance repair on existing concrete, not a new structural element, so no permit is required. If the lifting is being done in conjunction with structural repair to the foundation or interior perimeter drain installation, those adjacent scopes may have their own permit requirements which we handle. If a contractor tells you a poly lift needs a permit, ask them what code section — it is going to be a short conversation.
The foam cures to structural strength within 15 minutes, and the slab is walkable immediately after we finish the injection sequence. We usually let it sit for about an hour before we tell homeowners to drive on it, mostly to give the injection hole patches time to set. So a morning lift means you can park in your garage that afternoon. Foot traffic on a front stoop or walk lift is fine immediately — we walk on them ourselves as we patch the holes. Full cure on the foam is 30 days but that is metallurgical curing, not something that affects load bearing.
Free on-site Kannapolis inspection. Fixed written quote. Call (980) 227-1769 or book below.