How to hire a concrete contractor: questions, quotes, contracts

Step 1: know what kind of contractor you need

Flatwork contractors pour and repair driveways, patios, walks and slabs. Leveling contractors lift sunken slabs. Foundation repair companies install piers under houses. Decorative specialists do stamping, staining and overlays. Many firms do more than one, but few do all of them well. Match the firm to the job. If the problem involves your house's foundation, hire a structural engineer first, separate from any repair company. See finding a residential flatwork contractor.

Step 2: check licensing, registration and insurance

There is no single national rule, and licensing for concrete work is often local. Chicago, for example, licenses general contractors in classes by project size^[7]. Texas abolished its Residential Construction Commission, effective 2010, and has no state license for foundation repair contractors^[8]. Ask your city's building department what applies, then ask the contractor for proof. Whatever the license rules, ask for certificates of general liability and workers' compensation insurance. See contractor licensing by state and city.

Step 3: ask who pulls the permit

The model residential code lists sidewalks and driveways as exempt from a building permit^[2]. Cities still control their right-of-way. Wheaton, Illinois, for instance, requires a permit to build, repair or replace a drive approach or public sidewalk, and for a new driveway where none existed^[3]. Garage slabs, foundation work and structures on slabs usually need permits. The contractor should know the local rules and pull the permit. See do you need a permit for concrete work.

Step 4: compare quotes on the same scope

Price differences usually come from scope. Ask every bidder to state in writing:

• Slab thickness, and thickened edges if any.
• Base material and depth, and how it will be compacted.
• Reinforcement type, if any.
• Joint layout and spacing. NRMCA recommends joints no more than 24 to 36 times the slab thickness^[9].
• Concrete strength and air content.
• Finish, color and sealer.
• Removal and haul-off of old concrete, grading, permits and cleanup.
• How and how long the concrete will be cured.

See questions to ask a concrete contractor, comparing two concrete quotes and, for house slabs, questions to ask a foundation repair company.

Step 5: get it in writing

Some states require a written contract. Illinois requires one for home repair and remodeling work over $1,000^[6]. Even where it is not required, a contract should list the scope above, the price and payment schedule, the start and finish window, who pulls permits, change-order rules and the warranty. If you sign at your door, the FTC Cooling-Off Rule gives you until midnight of the third business day to cancel many sales of $25 or more made at home, with exceptions^[1]. States may add their own rights. See what a concrete contract should include.

Step 6: understand the warranty

Ask what the warranty covers and what it excludes. Many flatwork warranties exclude normal shrinkage cracks, since all concrete cracks. Leveling warranties often cover re-lifting the same slab, not new settling caused by drainage. Get it in writing. See concrete warranties: what is normal.

Timing the job

Weather matters. NRMCA says new concrete should be kept above 50 F and cured for at least 3 to 7 days^[4]. Pours in freezing or very hot weather need protection plans. A driveway pour takes about 1 to 3 days, plus 7 to 10 days before you drive on it, per HomeGuide^[5]. See best time of year to pour or repair and how long concrete jobs take.

Red flags

• Door-to-door offers of "leftover concrete from a job down the street."
• Cash only, or a large deposit before any materials are delivered.
• No written scope, or a refusal to say how thick the slab will be.
• Promises of "no cracks" because of mesh or rebar. NRMCA states mesh will not prevent cracking^[9].
• Pressure to sign today for a special price.

More in red flags and common sales tactics.

Every hiring guide

• Questions to ask a concrete contractor
• Questions to ask a foundation repair company
• Red flags and common sales tactics
• Comparing two concrete quotes
• Finding a residential flatwork contractor
• What a concrete contract should include
• Contractor licensing by state and city
• Do you need a permit for concrete work
• Concrete warranties: what is normal
• Best time of year to pour or repair
• How long concrete jobs take

When to call a pro

• Any new pour, replacement or lifting job beyond a small DIY patch.
• Before a contractor works near your house foundation: get a structural engineer's opinion first.
• When quotes differ widely, ask a third contractor to bid the same written scope.