My garage floor is cracked. Who do I call?
Usually, start with
Concrete repair professional
If the garage floor has cracks but does not appear noticeably displaced or sunken, a concrete repair professional commonly evaluates the slab condition and the type and extent of cracking.
Change course if
One side of the crack is higher than the other
Concrete leveling or structural expertise may also be relevant when the crack is accompanied by vertical movement.
Cracks continue into walls or other parts of the structure
A structural or foundation professional may be relevant when movement appears to extend beyond the slab.
Water comes through the crack or appears nearby
Drainage or waterproofing expertise may also be relevant when moisture is part of the condition.
Who handles what
Concrete repair
Evaluates cracking, surface condition, and repair options for the garage slab.
Concrete leveling
Evaluates slab sections that have changed elevation or settled relative to one another.
Structural / foundation
Evaluates movement that may involve more than the slab itself.
What might be happening
Concrete can crack for different reasons, and the appearance of a crack alone does not establish whether the slab is still moving. Crack width, displacement, pattern, location, and changes over time are useful parts of an evaluation.
Useful things to notice
Whether the crack is level on both sides
A height difference across the crack is useful information for the professional evaluating the slab.
Whether the crack is changing
Changes in width, length, or elevation over time are worth documenting.
Whether other parts of the garage show movement
Wall cracks, door changes, or gaps can help establish whether the condition is isolated to the floor.
Before you call
Take wide and close photographs of the crack and note whether the floor is level on both sides. If you have older photos, they may help show whether the condition has changed.
Before you fix the visible symptom
Filling a crack can improve its appearance but does not establish why it formed or whether movement is continuing. When there is displacement or broader movement, an evaluation before cosmetic repair can preserve useful evidence.
References
American Concrete Institute. Cracking in Concrete.
ACI Committee 224. Causes, Evaluation, and Repair of Cracks in Concrete Structures.
American Concrete Institute. ACI 201.1R-08, Guide for Conducting a Visual Inspection of Concrete in Service.