If you don't have a lot of traffic moving through your marble floors, you can wait two or even three years. One thing about marble you should be aware of is that marble is a calcium based stone like limestone and travertine and is susceptible to etching by any acidic liquid.
Sealing marble tile will not protect it from etching, so caution should be used with any acidic liquid (e.g. orange juice). In general, mopping tile floors regularly with a neutral floor cleaner and a flat mop, will be the best and easiest way to maintain the tile floors.
Sealing marble tile is not very complicated and if you take your time and clean it properly before you seal it, you shouldn't have any problems.
* First, you need to know if there are any topical coatings such as wax or polyurethanes on the marble tile, and if there is, it requires a stripping process, that's different than what it is described below.
** Clean your marble tile thoroughly with a neutral cleaner or if it's badly soiled, you can use an akaline stone cleaner to break down any dirt and grease build-up.
* Once the marble tile is clean, dry it with a cotton or microfiber cloth. It's very important the marble is dry before any sealer is applied. In some cases, if the marble is more porous, it may need 24 to 72 hours to dry before applying a sealer.
>>If you're sure the marble is completely dry, you can apply the sealer evenly using a lamb's wool applicator or any soft cloth. Honed or textured travertine will require more sealer due to it being more porous than a polished marble tile.
>>Not all sealers behave the same and if you're using a water based sealer, it will take longer to dry compared to a solvent based sealer. It's important not to let the sealer puddle up and dry on the surface as any unwanted residue can be difficult to remove from some stones.
>>Let the sealer absorb into the marble for at least 15 to 30 minutes not letting dry on the surface. You want to see the sealer beginning to dry on the marble, but not completely before removing any residue.
>>Depending on the porosity of the marble you can apply a second coat of sealer. Remove sealer residue with either a microfiber or cotton cloth, making sure to remove all excess sealer. You don't want to see any streaks left by the sealer
>>If you do see streaks left by the sealer, re-activate the sealer with some more sealer, and then buff off.
>>Try this sealer for all your stone surfaces, including granite countertops and granite tile.