What mudjacking involves
Mudjacking typically uses drilled access holes and a pumped cementitious slurry to fill space beneath a slab and help raise it. Hole size, material and the achievable result depend on the contractor’s system and the project.
What foam lifting involves
Polyurethane lifting uses injected material that expands beneath the concrete. Its behavior and suitability depend on the formulation, installation and site conditions. The fact that foam expands does not make it a universal solution.
How to evaluate the options
Ask which method the contractor actually offers, why it suits the slab, how access holes will be finished and what conditions could limit the lift. Consider the desired final slope and how adjacent panels will align.
What neither method automatically fixes
Neither injection method inherently repairs severely broken concrete, eliminates every drainage problem or guarantees that future soil movement will stop. A useful proposal explains both the intended result and the remaining risks.
When replacement enters the discussion
If the slab has extensive cracking, serious surface failure or an unsuitable base, removal and replacement may be more appropriate. The right comparison is between realistic scopes of work, not a blanket claim that one method always wins.