Questions to Ask a Concrete Leveling Contractor

What Should You Ask a Concrete Leveling Contractor?

Five questions do most of the work: is this slab a good leveling candidate, what caused the settling, which method do you recommend and why, how long until the area is usable, and what does the warranty cover. Concrete leveling is a specialized service where honest diagnosis of the slab condition and the cause of settling matters more than the lift itself. The answers determine whether you get an accurate assessment, a result that holds, and a straight answer when replacement is the better option.

Is This Slab a Good Candidate for Leveling, or Should It Be Replaced?

This is the most important question, and you should ask it directly. Ask the contractor to assess the slab and explain specifically why it is or is not a good leveling candidate. (For more on this, see How to Find the Best Concrete Leveling Contractor.)

The slab is a good candidate when it is structurally sound without through-cracks, when the settling comes from voids beneath it rather than slab failure, and when the concrete is not severely deteriorated. It is a poor candidate when the slab is cracked through its full depth, significantly scaled or spalled, or old enough that lifting may cause it to fracture.

A contractor who recommends leveling for every settled slab regardless of condition, without that assessment, is prioritizing the service call over your interest. Ask multiple contractors the same question and compare the recommendations. A good contractor will tell you when replacement would serve you better. (For more on this, see Concrete Leveling vs. Slab Replacement: How to Decide.)

What Caused the Settling, and Will It Recur?

Ask whether the contractor is identifying the cause of settling as part of the assessment, not just the symptom. If water erosion is the cause and it is not corrected, the slab is likely to resettle after leveling.

Some causes are correctable. Extending a downspout to direct water away from the slab removes the cause and prevents re-settling. Others are ongoing: expansive soils and active tree roots will keep working after the lift, and you should understand that before investing in leveling. A contractor who identifies the cause and recommends correcting it alongside the lift is providing more complete service than one who raises the slab and considers the job done.

Which Method, and How Soon Can You Use the Area?

Mudjacking or Polyurethane Foam, and Why

Ask which method the contractor is proposing and why it fits your specific application. Traditional mudjacking injects cement grout through larger holes. Polyurethane foam injection uses smaller holes and a lighter material. Both produce comparable results for most residential applications, so the answer should reference something specific about your job: the slab’s condition, the required cure time, the site’s groundwater conditions, and whether the appearance of the drilled holes matters on that surface. A contractor who recommends the same method on every job without explaining the reasoning is not tailoring the approach to your situation.

Curing and Return to Service

Confirm the curing requirement for the method being used. Polyurethane foam cures in minutes and the area is typically usable the same day. Mudjacking grout requires 24 hours of curing before vehicle traffic. Planning around that window prevents inadvertent use that would compromise the result.

Warranty and Written Scope

Ask specifically what the warranty covers, how long it lasts, whether it covers re-settling of the treated area, and what the claims process is. Established concrete leveling contractors typically warranty their work for 1 to 3 years against re-settling in the treated area, and some warrant against resettlement for as long as 5 years. Get the terms in writing, and confirm what counts as covered resettlement versus normal slab movement. A warranty of less than one year on a $1,000 to $2,000 project is not meaningful protection. Confirm the warranty applies to the specific treated area, not to adjacent slabs that were never lifted. (For more on this, see How to Find the Best Concrete Leveling Company.)

The written contract should also specify the exact scope of work, the cost and payment schedule, the timeline, warranty terms for labor and materials, and the process for handling scope changes. For any project over $500, written scope is non-negotiable. Tie payments to milestones: a deposit at signing, a payment at project start, and a final payment at completion after a walkthrough. A contractor who requires full payment upfront is a red flag in any trade.

The Red Flag Question

One additional question quickly reveals a contractor’s quality orientation: ask what the most common reason is that projects like yours fail prematurely. A contractor who gives a specific, knowledgeable answer, such as inadequate base preparation on a driveway or the wrong spring selection on a garage door, has thought about failure modes and how to prevent them. One who cannot answer clearly, or who says failures are rare without specifying how they avoid the known causes, has not.

Preparing Before the Contractor Arrives

The most productive contractor conversations happen when you come prepared: a clear description of the symptom, the questions above written down, and any relevant documentation such as the age of the slab, previous service records, and unusual site conditions.

Get at least two or three quotes, and make sure they are for the same method and the same treatment area so you are comparing equivalent scope. Verify current general liability insurance and, for any work with crews on your property, workers compensation coverage; licensing requirements vary by state, so confirm what applies in your jurisdiction. Compare more than price: the contractor who gives the most thorough assessment of slab condition and settling cause is usually the one providing the most reliable service.

Record the answers, or ask for written confirmation of warranty terms, scope inclusions, and timeline. The most common sources of conflict after a project are scope items discussed verbally but never confirmed in writing, and warranty coverage the two parties understood differently.