Select and time semi-rigid joint filler installation for a polished concrete floor

Steps

1. Confirm the joint filler is a semi-rigid product (typically epoxy or polyurea based) intended for hard-trafficked, polished floors rather than a flexible sealant meant for exterior movement joints, since the two serve different purposes.
2. Where practical, wait until the slab has substantially completed its drying shrinkage before final filling, or plan a two-stage fill (initial fill, then a final top-off/grind-flush pass), since fresh joints continue to open as the slab dries.
3. Fill joints flush to, or very slightly proud of, the finished floor surface so the filler can be ground flush during polishing rather than left low, which creates a recess that collects dirt and invites edge spalling under forklift/pallet-jack traffic.
4. Confirm the filler manufacturer's cure time before grinding over it, since grinding an under-cured filler can smear or tear it out of the joint.
5. Sequence joint filling within the overall grind/polish schedule so the filler is ground and polished along with the surrounding slab rather than as an isolated later step.