Short answer

Hairlines are common and often cosmetic. A crack becomes a safety or durability issue when it is wide, stepped, growing, or linked to settlement or heave.

Simple thresholds

• Width near a quarter inch is worth evaluation
• Any vertical step is a trip hazard and can damage wheels and carts
• Rapid change in one season suggests active movement

What to do

• Seal and monitor small stable cracks
• Call a pro if you see widening, a step, rocking panels, or voids
• Correct causes before choosing any finish

After the fix

If the slab is sound but looks rough, choose a finish that fits moisture and salt exposure.

Where a breathable stone and epoxy surface such as Nature Stone fits

It is a finish layer for a stable slab. It hides small flaws, adds traction, and remains easy to clean while allowing moisture to pass.

FAQ snippet
Q: Can a finish layer fix structural cracks
A: No. Fix settlement or heave first. Then select the surface you want.