Injection Repair Cost vs Replacing Large-Format Tile

Injection repair means drilling a few small ports into the grout joints around a hollow-sounding tile, injecting epoxy or polyurethane resin into the void underneath, and sealing the ports. Most contractors price that at $150–$400 per spot, and the work itself runs 1–2 hours of labor once the tile is identified and marked. There's no demolition, no matching tile to source, and no grout color to reproduce across a patch.

Replacing a single large-format tile is a different job entirely. The installer has to score and pry the tile free without cracking its neighbors, scrape old thinset off the substrate, re-level if needed, set the new tile, and let it cure before grouting — which typically spreads the work across two visits because thinset needs about 24 hours before it can take grout and foot traffic. All in, that's 4–8 hours of labor and $300–$600 per tile once material, disposal, and the second trip are counted.

Split the difference on both ranges and injection repair comes out close to 40% cheaper than replacing one tile outright — before anything goes wrong with the removal.

Injection repair only fixes a void — a pocket of air or failed mortar under a tile that still sounds hollow but hasn't cracked. If the tile itself is chipped, cracked, or lippage has already shifted it out of plane, resin injected underneath won't fix any of that, and replacement is the only real option.

Tile size matters more than people expect. Anything with an edge of 15 inches or longer counts as large-format under the TCNA Handbook, and those tiles are harder to pry out cleanly than a 12x12. Field reports from installers put the odds of cracking an adjacent tile during removal at 30–50%, which means a single-tile replacement job can turn into a two- or three-tile job mid-demo, multiplying that $300–$600 figure before the installer even reaches for new material.

Where the tile sits changes the stakes too. In a shower or tub surround, a hollow spot often means the waterproofing membrane underneath has failed, not just the bond coat. Injecting resin seals the void but doesn't restore a broken moisture barrier, so wet-area repairs need a diagnosis of what's under the tile before anyone commits to the cheaper fix. If a full wet-area re-tile is on the table, running the numbers through the /bathroom-tile-calculator before scheduling anything gives a realistic material and cost baseline to compare against the repair quote.

Availability of a matching tile is the quiet factor that tips the decision. Discontinued runs and dye-lot variation mean a five-year-old large-format tile often can't be replaced with an exact match, even if the installer can pull it out cleanly. When that's the case, injection repair becomes the only option that doesn't leave a visibly mismatched tile in the middle of the floor — or the job scope grows to re-tiling the whole run instead of swapping one piece.

A hollow-sounding tile that gets left alone doesn't stay stable. Foot traffic keeps flexing the unsupported tile until the bond fails completely, the tile cracks, and the grout around it starts to crumble and spread the problem to neighboring joints. At that point the $150–$400 injection fix is off the table, and the job shifts to full-room retiling priced at $7–$14 per square foot in labor alone — on top of material, which scales with the whole floor instead of one tile.

Waiting also increases the odds of collateral damage. Once a cracked tile has to come out instead of being caught early, that same 30–50% chance of cracking adjacent large-format tiles during removal applies, except now it's happening on a floor that's already lost its matching stock. Each additional tile that cracks during demo adds another $300–$600 replacement to a bid that started as a single-spot repair.

Before deciding between a patch and a tear-out, it's worth pricing both ends of the range. Running the room's square footage through the /floor-tile-calculator shows what a full re-tile would actually cost if the hollow spot has already spread, and /guides/calculating-tile-replacement-costs breaks down the line items — tile, thinset, grout, labor, disposal — that make up that per-square-foot figure so the comparison isn't just a guess.