Most tile & grout brushes are intended to be used with the sprayed-on cleaner remaining unabsorbed on the surface of the tile. Such paving materials as brick and bluestone won't really clean well, since the cleaning solution will rapidly absorb into the stone. And if you keep spraying, you will leave a soapy mess, unless you are carrying some sort of extractor that will let you suck up the residue. I have a regular carpet customer with a lot of bluestone flooring that she likes to have cleaned once a year. I then call the guy that I use to do marble refinishing and related stone work. He comes in, does the work, and sends me a referral fee. Works better this way.