Flooring Tile - Partial replacement ceramic tiles

I have a ceramic tile floor, about 5 years old that is in excellent condition - except for an area about 100 SF ruined by some flooding. At the minimum I need to replace that area and replace the plywood underlayment as well.

I had been considering replacing the entire 400 sf area at significant expense. We will hire a contractor to do the work. We thought it would be too hard to match up the old and the new sections of tile and it would look bad.

But we really like the existing tile look and most of it (75%) is in great shape. The exact same tiles are still available, and I know the exact grout mixture that was used. How possible is it to match these up so it looks like it was all done at the same time.

If it is not perfect, I figure I can have all 400 sf of the grout colored, and then it would be a perfect match. Does this seem right?

About how much does grout coloring cost per sf? I think I paid a little less than $1/sf to have it sealed a couple years ago. $2 for a coloring and sealing?

Thanks in advance, it would be helpful to hear some opinions from those in the know.

How possible is it to match these up so it looks like it was all done at the same time.

While it may seem like the tile should match perfectly, that probably won't be the case. Most often the same tile, same color but different lot will be noticably different. Also depending upon how long you have had the original tile and what you have done to it, and how it has worn may also be noticeable when compared to the new tile.

If it is not perfect, I figure I can have all 400 sf of the grout colored, and then it would be a perfect match. Does this seem right?

Probably not. You mentioned that you had the grout sealed in the past. Sealer, clogs the pores of the grout, preventing staining and slowing down moisture absorbtion. That sealer will slow down the absorbtion of the grout colorant and it will likely not be a good match with the new grout.

About how much does grout coloring cost per sf? I think I paid a little less than $1/sf to have it sealed a couple years ago. $2 for a coloring and sealing?

Depends on a lot of factors. I doubt you'll get someone to quote this on some per foot rule of thumb without seeing it, knowing the facts and exactly what they will be up against. As stated this will be difficult to get the old to match the new grout.

thanks. i was not aware that matching of tiles woulf not be possible for different lots. I'll replace the whole thing then...