What slab lift is and how you start the paper path

Last updated 2026-08-21

What is slab lift?

Slab lift is raising a concrete slab that has settled, then filling the void so the slab sits where you need it. You drill ports, inject a carrier, and watch the elevation. That is the job.

People use two carriers. Cementitious grout (often called mudjacking or slab jacking) is a slurry pumped under pressure. Expanding polyurethane foam is a two-part mix that reacts under the slab and lifts as it grows. Highway shops have used grout jacking for decades on concrete pavement. House driveways and sidewalks are the same physics at a smaller scale. The National Concrete Pavement Technology Center preservation guide treats slab stabilization and jacking as ordinary pavement tools, not a novelty. ^[1]

You are not replacing the slab. You are not pouring a new driveway. You are moving what is already there. That is why the paper path looks like repair contracting, not like a ready-mix plant.

A good lift has three checks. The high point of the slab is still sound. The soil or base under it can take the new load. The edges and joints will not shatter when you put pressure under them. Fail any of those and you are in replacement territory. I walk those jobs. So should you.

Residential work is usually driveways, garage floors, pool decks, sidewalks, and patio slabs. Commercial work adds warehouse floors and dock approaches. Public work adds sidewalk trip edges. The 2010 ADA Standards allow a vertical change in level of 1/4 inch maximum if it stays vertical. ^[2] Cities care about that number even when a homeowner does not.

Slab lift is construction. Silica dust from drilling, isocyanates from foam, and slurry splash from grout are not theoretical. Treat them as job hazards from day one.

How do you start slab lift?

You start on paper, not on a truck. Confirm whether the state and the city treat slab raising as licensed contracting. Form the business. Get a free EIN from the IRS. Open a bank account that is not your personal checking, and buy insurance that matches the contracts you will sign. Hire or stay solo. Write a simple OSHA file with SDS sheets, hazard communication, silica controls, and a respirator plan if you will use respirators. Only then do you spend money on a drill and a pump.

That order is boring. It is also how you stay legal when a GC asks for a certificate of insurance on Friday.

The IRS says, "Applying for an EIN is a free service offered by the Internal Revenue Service." ^[3] Use the IRS page. Do not pay a reseller.

Business structure is a tax and liability choice. The SBA walks through sole proprietorship, partnership, LLC, and corporation in plain language. ^[4] I am not your lawyer. Most small crews pick an LLC because they want a liability box and a simple tax return. Confirm that with a CPA in your state.

Licensing is the part national blogs get wrong. There is no national slab lift card. California treats a person who undertakes to construct, alter, repair, or improve a structure for compensation as a contractor, subject to the exemptions in the Contractors State License Law. ^[5] Florida defines contractor in s. 489.105, F.S., as the person who, for compensation, undertakes to, submits a bid to, or does construct or repair, except as exempted. ^[6] Texas does not run a statewide general contractor license the way those two states do. Confirm with the board that will actually fine you, and confirm the current dollar threshold if the state has a minor-work exemption.

Want a mix-yield and bid-per-sqft worksheet already built? SlabLiftPath publishes a $149 one-time Mix + Bid-per-Sqft Kit at /start. A blank spreadsheet does the same math if you are cheap and careful.

Is slab lift the same as mudjacking or foam lifting?

Mudjacking is one way to do slab lift. Foam lifting is the other common way. Same goal. Different carrier, holes, weight, and chemical file.

I would not buy both a foam rig and a mud pump in year one. Pick the work you can sell. Foam wins indoor slabs and HOA driveways where small ports matter. Grout wins when the void is huge and the owner will not pay foam prices. If you cannot sell either yet, rent.

Highway grout jacking sits in ordinary pavement preservation practice. ^[1] The U.S. Army Corps of Engineers repair manual treats pressure grouting as a concrete repair method, not a parlor trick. ^[12]

Question	Polyurethane foam	Cementitious grout
What you pump	Two-part foam that expands	Slurry of cement, soil or sand, and water
Ports	Smaller drilled ports	Larger holes
Weight you add	Low	Higher
Cleanup	Drill dust and foam trim	Slurry splash and leftover mud
Extra hazard to plan	Isocyanates [8] [9]	Silica in the mix and the dust [7]
Where it still wins	Tight indoor slabs, load-sensitive soils	Big outdoor slabs, cheap fill volume

Do not tell a homeowner foam is "permanent" and grout is "temporary." Both fail when the soils keep moving or the slab was already broken. Sell the lift you can stand behind, then write the limit in the contract.

What licenses do you need before you bid a slab?

You need whatever contractor classification your state and city assign to concrete repair for pay, or a written exemption you can show a building official. You also need the local business tax or registration if the city runs one. That is the whole license answer. The rest is looking it up.

California publishes classification descriptions, and C-8 Concrete is the usual conversation for forming, placing, and finishing concrete. Slab raising on existing flatwork may land there, under a related specialty, or under a B general building license if the contract wraps other trades. Confirm the class with CSLB before you print cards. ^[13] Florida chapter 489 is the contractor statute. Read the definition and the exemptions, then ask DBPR which license they want for driveway raising in your county. ^[6]

I would not assume a handyman card covers a garage floor lift. Boards do not care that you only drilled six holes.

Some states have no statewide general contractor license. Cities there still license businesses and pull permits. Confirm both layers.

Renewal is its own calendar. If you already hold a card, keep slab lift renewal in california, slab lift renewal in florida, and slab lift renewal in arizona on a list next to insurance. Confirm the current fee and the late penalty with the board. I will not invent either number.

Bond and judgment disclosure rules ride with some licenses. Read the application. Do not skip the background questions.

What insurance actually matters in year one?

You need insurance that matches the contracts you will sign, plus whatever your state requires if you have employees. That is usually commercial general liability, hired and non-owned auto or a commercial auto policy, and workers compensation once you have staff. Inland marine on the rig is how you sleep if the proportioner gets stolen.

I will not invent a legal minimum limit. Many GCs ask for $1 million per occurrence on CGL. That is a contract term, not a federal statute. Confirm the limit, additional insured wording, and waiver of subrogation with the broker and the GC. A personal umbrella from your car insurance friend is not a jobsite policy.

Store drums of isocyanate and polyol? Ask about contractor's pollution. Ordinary CGL forms get picky about fumes and cleanup. Confirm the form. Do not guess from a forum post.

Workers comp is state law when you have employees. Solo owner exemptions exist in some states and not in others. Confirm with the state fund or your agent. OSHA still applies to you either way if you have employees. If you are truly alone, you still have silica dust and isocyanates in your lungs. Buy the controls anyway.

Certificates of insurance are part of the paper path. Build a habit of sending the COI before mobilization. GCs will not wait while you call the agency from the driveway.

What OSHA and chemical rules hit a foam crew?

Drilling concrete makes respirable crystalline silica. Pumping two-part polyurethane puts diisocyanates in the air and on skin. Both can happen on the same driveway before lunch.

OSHA 29 CFR 1926.1153 sets the respirable crystalline silica PEL for construction at 50 μg/m3 as an 8-hour TWA, with an action level of 25 μg/m3. ^[7] The rule says, "This section applies to all occupational exposures to respirable crystalline silica in construction work, except where employee exposure will remain below 25 micrograms per cubic meter of air (25 μg/m3) as an 8-hour time-weighted average (TWA) under any foreseeable conditions." ^[7] Table 1 tasks can keep you in a prescribed-control box if you follow them. Freelance your own method and you own the exposure assessment.

NIOSH has warned for decades that diisocyanates cause asthma and other respiratory disease. The NIOSH alert on diisocyanate exposure states they "are widely used in the manufacture of flexible and rigid foams, fibers, coatings such as paints and varnishes, and elastomers." ^[8] EPA publishes an MDI fact sheet because MDI is a building-block chemical in those foams. ^[9] Read the SDS for the exact system you buy. Do not run a competitor's SDS.

Respirators required? 29 CFR 1910.134 wants a written program, medical evaluation, and fit testing. ^[10] Construction PPE duties sit in 29 CFR 1926.95. ^[11] I would rather spend money on ventilation, gloves, and a real respirator program than on a vinyl truck wrap.

Blowing agents in foam systems have been moving under the AIM Act HFC phasedown. Confirm what is in the current drum with the supplier and the SDS. Do not assume last year's blend is still legal to stockpile the way you want. ^[14]

What first-year equipment is worth buying?

Buy the tools that let you measure, drill, inject, and leave the site clean. Rent or lease the expensive injection plant until you have a repeatable book. Buying iron first is how people starve.

Day-one kit I would actually own: a rotary hammer or core drill that matches the port size, ports and tap-in fittings, two ways to read elevation (a rotary laser and a backup digital level), a generator or a truck that can run the plant, PPE that matches the SDS, a spill kit, and a shop vac. That is enough to start if the plant is rented.

I would not wrap the van. I would not buy a second mixer. I would not finance a trailer I cannot fill with sold work. I would buy a real laser, because overlift is how you crack a garage floor and then work for free.

Foam plants and grout pumps are different machines. Do not let a salesperson talk you into a "does everything" skid before you know which carrier you can sell. The Corps repair guidance and the pavement preservation guide both treat grouting as a controlled process, not a blast of material. ^{[1] [12]} Control is the skill. The machine is just a pump.

Used equipment is fine if you can get parts and a manual. Orphaned custom trailers are a waste. Confirm voltage, hose lengths, and spare gun parts before you wire the money.

How should you bid a slab lift job?

Bid from yield, holes, hours, travel, patching, tax, and a profit you can live on. Do not bid from a national average you saw on a lead site. Nobody has a trustworthy public dataset for residential slab lift prices. The closest honest method is your own job-cost file after ten paid slabs.

Start with the area and the estimated void. Foam is sold by the set or by the pound, grout by the yard or the batch. Convert that to dollars on the ground, then add drill time, cleanup, and the hour you will spend talking to the owner about a crack that was already there. What slab lift cost looks like before you bid work is the mindset. Slab lift cost in Colorado is a reminder that travel and weather change the same math in one market.

I price mobilization as its own line. Buried mobilization is how you work a 40-mile driveway for free.

Write what you will not lift. Post-tension slabs you cannot map, brick that will shear off a rising stoop, and owners who want four inches on a shattered patio do not belong on a cheap bid. Put the elevation target in the contract. Take before and after shots with a tape in the frame.

Want a prebuilt mix and bid-per-sqft worksheet? The buyer check on mix and bid-per-sqft kits is the next read. Build the same sheet yourself if you would rather not spend the money.

What permits and site rules show up on houses and sidewalks?

A private driveway often needs no building permit. A city sidewalk often needs a right-of-way permit, traffic control, and a final grade that meets the city's trip standard. HOA work may need a letter before you drill. Confirm all three. I will not quote a city fee I cannot see.

The 2010 ADA Standards, section 303.2, say a vertical change in level of 1/4 inch high maximum shall be permitted to be vertical. ^[2] Section 303.3 lets a slightly taller change be beveled. Public sidewalks live in that world even when the homeowner hired you to "just lift the panel." Leave a new lip at the city walk and you created a problem.

Utilities are your problem before you drill. Call the locate number in that state and wait the required time. Garage slabs hide water lines and radiant tubing that locates will not mark. If the owner cannot tell you what is in the slab, slow down or walk.

Dumping leftover grout in a storm drain is how you meet the city the hard way. Foam trimmings and empty drums follow the SDS and the waste rules that apply to your size. Very small quantity generator rules live in 40 CFR 262.14 if you are actually in that box. Confirm. Do not guess from a Facebook group. ^[15]

What records should you keep after every lift?

Keep the job ticket, the signed scope, before and after elevations, photos, the product lot or batch, the SDS revision you used that day, and a copy of every COI you sent. That file is how you answer a board, an insurer, or an owner who swears the crack is new.

I keep a one-page elevation sketch. Corners, midspans, and the high point you refused to pass. If you cannot show the numbers, you cannot defend the lift.

Chemical records matter more on foam jobs. Diisocyanate exposure claims are ugly. NIOSH documented asthma and death risks from these chemicals years ago. ^[8] Your defense is training, PPE, and a paper trail, not a memory that "we always wear gloves."

License renewals, workers comp audits, and GC prequal forms will ask for the same stack again. Slab lift renewal in colorado and slab lift renewal in alabama are the kind of calendar items that sneak up while you are on a driveway. Confirm dates with the board.

Digital is fine. A folder named by address and date is enough. Fancy software is optional.

When should you walk away from a slab?

Walk when you cannot predict the move. Active structural cracks, a slab you suspect is post-tensioned and cannot map, brick or stone that will shear off a rising stoop, a garage with unmarked plumbing in the slab, and owners who want a cosmetic lift on concrete that is already rubble. I would rather lose the bid.

Replacement is the honest product on those jobs. Pressure under a shattered panel makes more shattered panel. The Corps repair manual is about evaluation first, then a method that fits the damage. ^[12] That order still works on a patio.

Indoor warehouse floors with rack loads are not a first-year special. Neither is a pool deck that ties into a vanishing edge. Get help or pass.

Overlift is a walk-away condition in real time. If a corner jumps and a joint starts to spall, stop pumping. You can grind a small high spot. You cannot uncrack a bay window wall you shoved.

Write the walk-away in your estimate template so you say it the same way every time. Tired sales talk is how bad slabs get sold.

What does a realistic first-year paper path look like?

Week one is entity, EIN, and a bank account. The EIN is free on the IRS site. ^[3] Week two is a call to the contractor board and a read of the classification text, plus the city business desk. Confirm the fee, the test, and the bond on that call. I will not invent processing days.

Week three is insurance quotes and the OSHA binder. SDS, hazard communication, silica, and respirators if you need them. ^{[7] [10]} Week four is equipment that matches the first sold job, not the brochure.

Sold work comes after you can hand a GC a COI, a license number or a documented exemption, and a contract that states the elevation target. Marketing before that is noise.

Year one waste I would skip: franchise pitch decks, lead-site exclusives you cannot convert, and any course that promises a license timeline. Boards do not honor course promises.

Keep the renewal list next to the insurance list. States do not share a calendar. Work across a border and you may hold two cards. Confirm each one.

SlabLiftPath is an independent publisher, not a law firm and not a service company. We do not bid your jobs and we do not pull your license. Use this as a reference, then confirm the live rule with the board, the IRS, OSHA, and your broker.

Frequently asked questions

What is slab lift?

Slab lift is raising a settled concrete slab by injecting grout or expanding polyurethane under it, then filling the void so the panel sits on a new grade. You are repairing location, not pouring a new slab. Highway shops have used jacking and stabilization for decades. The same method shows up on driveways, sidewalks, and garage floors.

How do you start slab lift?

Start on paper. Confirm the contractor classification where you will bid, form the business, get a free IRS EIN, open a business bank account, and buy insurance that matches the contracts. Build an SDS and silica file before you drill. Then rent or buy a drill and an injection plant. Confirm every fee with the board. Nobody can promise a processing time.

Do I need a contractor license to lift a driveway?

Often yes, once the job is construction for compensation and it clears your state's small-job exemption. California and Florida both define repair-for-pay as contracting, with listed exemptions. Other states skip a statewide general license and still let cities regulate you. Confirm the class and the current dollar threshold with the board that will fine you.

Is slab lift the same as mudjacking?

Mudjacking is slab lift that uses a cementitious slurry. Foam lifting is slab lift that uses expanding polyurethane. Same goal, different holes, weight, cleanup, and chemical hazards. I would pick one carrier in year one based on the work you can actually sell, then rent the other if a job needs it.

How much does it cost to start a slab lift business?

Nobody publishes a solid national startup total. Your real stack is entity filings, license and bond if required, insurance, a drill and levels, PPE, and either a rented or purchased injection plant. Confirm filing fees with the state. I would rent the plant until the book is real. Fancy trailers and wraps can wait.

Can I do slab lift as a sole proprietor?

Yes, if your state allows that structure for the license you need. The SBA outlines sole prop, LLC, and corporate choices. An LLC is the usual small-crew pick for a liability box, but that is not legal advice. Get a CPA and, if the board requires it, the exact entity type printed on the license application.

What chemicals are in polyurethane slab lift foam?

Typical systems are a polymeric isocyanate side (often MDI-based) and a polyol resin side that foams when they mix. NIOSH treats diisocyanates as asthma hazards. EPA publishes MDI fact sheets for that family of chemicals. Read the SDS for the exact drums on your truck. Blowing-agent rules have been changing under the federal HFC phasedown.

Does OSHA apply if I work alone?

OSHA's construction silica and respirator rules are written around employee exposure. A true one-person shop may sit outside some employer duties, but the dust and the isocyanates are still in your lungs. Hire anyone and the full program comes with them. I would run the controls either way.

Do I need a permit to lift a city sidewalk?

Often yes. Private driveways may need nothing. City walks usually sit in the right-of-way and need the city's permit, traffic control, and a finish that meets the trip standard. The 2010 ADA Standards cap a vertical change at 1/4 inch if it stays vertical. Confirm the permit desk before you drill public concrete.

How long does foam take to set?

Most two-part lift foams reach handling strength in minutes, then keep gaining strength as they cool. I will not quote a brand cure time I cannot cite from your TDS. Read the data sheet for the system you bought, then stay off the slab until that sheet says you can. Grout is slower and weather-sensitive.

What happens if I overlift a slab?

You can crack the panel, open a joint, rack a door, or shove a wall that was sitting on the slab. Stop pumping the moment a corner jumps past the target. Take elevations as you go. A cheap laser pays for itself the first time it saves a garage floor. Write the target elevation into the contract.

Do I need workers comp with no employees?

Maybe not, depending on the state and on whether owner exemptions exist. Some states still want a policy or a formal waiver. GCs may require a certificate anyway. Confirm with the state fund or a broker who writes construction. Do not take a forum answer as the rule.

How do I dispose of leftover iso and polyol?

Follow the SDS and the hazardous waste rules that apply to your generator size. Empty drums and unused resin are not household trash. 40 CFR 262.14 is the federal very small quantity generator box if you truly fit it. Confirm with your state environmental agency. Never dump leftovers in a storm drain.

What classification is slab lift in California?

CSLB publishes classification descriptions, and C-8 Concrete is the usual starting conversation for concrete flatwork. Some jobs may sit under a related specialty or a B general if other trades are in the contract. Confirm the class with CSLB before you advertise. Confirm the current minor-work dollar line too, because statute can move it.

Sources

1. National Concrete Pavement Technology Center, Concrete Pavement Preservation Guide, 2nd ed.: Slab stabilization and slab jacking are documented concrete pavement preservation methods.
2. U.S. Access Board, 2010 ADA Standards section 303: Vertical changes in level of 1/4 inch high maximum are permitted to be vertical.
3. IRS, Apply for an Employer Identification Number (EIN) online: Applying for an EIN is a free service offered by the Internal Revenue Service.
4. U.S. Small Business Administration, Choose a business structure: SBA outlines sole proprietorship, partnership, LLC, and corporation as startup structure choices.
5. California Business and Professions Code section 7026: California defines contractor to include persons who undertake to construct, alter, repair, or improve structures for compensation.
6. Florida Statutes s. 489.105 (2023): Florida defines contractor as a person who, for compensation, undertakes or bids to construct, repair, or alter, except as exempted.
7. OSHA 29 CFR 1926.1153 Respirable crystalline silica: Construction silica PEL is 50 μg/m3 as an 8-hour TWA, with a 25 μg/m3 action level.
8. NIOSH Alert 96-111, Preventing Asthma and Death from Diisocyanate Exposure: Diisocyanates are widely used in flexible and rigid foams and are linked to asthma and other serious respiratory disease.
9. EPA, Methylene Diphenyl Diisocyanate (MDI) and Related Compounds Action Plan: EPA identifies MDI as a building-block chemical used in polyurethane foams and coatings.
10. OSHA 29 CFR 1910.134 Respiratory protection: Required respirator use needs a written program, medical evaluation, and fit testing.
11. OSHA 29 CFR 1926.95 Criteria for personal protective equipment: Employers must provide and require PPE when hazards are present in construction work.
12. U.S. Army Corps of Engineers EM 1110-2-2002, Evaluation and Repair of Concrete Structures: Pressure grouting is treated as an evaluation-first concrete repair method.
13. CSLB, Description of Classifications: CSLB publishes official descriptions of contractor classifications, including C-8 Concrete.
14. EPA, Frequent questions on the phasedown of hydrofluorocarbons: The AIM Act HFC phasedown affects production and use of listed hydrofluorocarbons, including some foam blowing agents.
15. eCFR, 40 CFR 262.14 Conditions for exemption for a very small quantity generator: Federal VSQG conditions limit how small quantities of hazardous waste may be managed and disposed.