Cleaning Fire Damaged Limestone

[Tileworks]

Looking for advice on how to clean fire damaged unfilled limestone. The client tells me the tiles were never sealed although it's difficult to confirm this and the fire was a plastic based fire in the basement affecting the ground floor entrance floor tiles. It's difficult to say how much of the damage is fire related and how much is dirt and wear as they weren't grouted very well and alot of the pit marks are filled with dirt and crud. Looking for cleaning solution recommendations and techniques and also whether steam cleaning would be a good option?
Thanks in advance

 

[Dan]

I honestly don't know what to suggest. I'd try small amounts of everything and test a lot. Worst case scenario they need to come up anyway so testing a lot perhaps won't hurt too much.

@Lithofin BOB might have an idea or two..?

 

[Lithofin BOB]

All about the testing, I would test a solvent based alkali cleaner, we have lithofin wexa, dilute this 1-2 and test two stones, keep wet for 12-15 mins scrubbing with a stiff brush or white pad every min. Rinse this with water and re apply if required. If real stubborn contaminants or staining try a stripping agent after you have de-greased the floor as above . Spot clean with the stripper, we have wax off. If any remaining deep oil marks you could try a poultice we have oil- ex. After the floor is fully dry ( min 7-9 days or until fully dry) re- impregnate

If you have any photos of this floor I could be more precise on cleaning agents req.

 

[Dan]

How did you get on with this?

 

[jonnyc]

Very difficult to remove smoke fire stains in my experience. Once laid some Bulgarian white limestone floor and walls in a bathroom in a.africa. Night security made a fire on the tile floor to keep warm !!!!and smoke turned whole bathroom
Puce yellow. Tried everything inc the Cape Town tile doctor! Ended up doing a runner back to uk before I got accused and hung up

 

[Dan]

Wise move I guess.