Observe runoff during rain
Notice whether water pools in the middle, flows toward the house or collects near a doorway. Downspouts and surrounding landscaping may also contribute. Describe these observations when requesting an assessment.
Check the relationship to the building
The desired finished elevation must account for doors, siding, steps and other adjoining features. Raising one edge without considering the whole patio can create a new mismatch.
Understand what lifting can change
Where suitable, lifting may alter the elevation and slope of an existing slab. It does not automatically redirect roof runoff or correct every surrounding grading issue.
When a broader repair is needed
Severe cracking, poor underlying support or ongoing drainage problems may call for replacement or additional site work. Ask what the contractor proposes to do about the water source as well as the low concrete.
Prepare useful information
Approximate dimensions, photos after rainfall, the location of downspouts and the direction of the slope can help start a productive conversation.