It's always an extra and not a part of a standard job. Nothing is included that isn't written into the contract. If you don't have a written contract, there may be more surprises to come from your assumptions. If you have a written contract, now is the time to read it again.

I discuss sealers with clients, but rarely include them in the proposal unless I am expressly asked to. That being said, I always list "Sealers" in my proposals and clearly describe that I will or will not be installing a sealer, where it will or won't be installed, and what quality of sealer is to be installed, if any. Most often, I simply explain to my clients how the sealer is applied and offer to purchase it for them at my cost, and let them do it themselves.
If it's not in writing, it's not part of the contract, I'm afraid.
Shaughnn

I have to wonder if it's worth doing and agree with Mongo. I recently saw a large and beautiful tile installation at a family member's home. It's about a year old, and the traffic patterns are obvious even with a good sealer. Not sure how you could avoid that. OTOH, in the bathroom (where most of us are padding around in slippers or bare feet), the grout looks untouched. I have the same scenario in my home (the traffic patterns, not the new and beautiful tile installation). :)

Thank you so much for your comments and advice. Mostly I'm interested in the sealer for the bathroom in which we used bright white grout. I think we may have excess minerals in our water (copper pipes?) and I've been noticing a faintly orange tinge that I'm able to clean off, but I'd like to prevent it from staining permanently.

What I'm about to say puts me in the minority of tile pros, but I'll say it anyway. As far as I'm coincerned, sealing grout is the biggest scam this industry has going. Even sealed grout, sooner or later will show wear paths in high traffic areas. It will still stain from fine particulates. And it will still darken somewhat with age. The only thing sealer does (and that's with the good quality sealers) is put off the inevitable a bit. What goes alot further toward not having these problems (or atleast not seeing them) is using medium to dark grouts in high traffic areas, or places that might tend to get dirty or stained easily.

Again, I'm in the minority, but that's my two cents. My grandfather was a tile contractor, as was my father, my uncle, and my sister, and of course most of you know I am, as well. My father had 2 sisters (as well as his brother), and I've got 4 sisters and a brother, not to mention the assorted cousins, and NOT ONE of us has EVER sealed a single bit of grout (other than that in marble tile or slate, where the stone got sealed) in any one of our homes thru the years.

Thanks, bill vincent. I was about to get on to my contractor for not including sealing, and then planned on having to do it myself, after watching a time-consuming youtube video regarding such. I'll go with your expert advice and skip it. My grout is rather medium colored anyway. Thanks for posting. Love pros.