We were called out to look at this new Black Limestone patio in Ashford which was not looking as it should. The client had laid it himself but unfortunately had not managed to polish off all the grout from the surface of the Limestone thereby degrading the appearance of the stone.
Grout Smearing or Grout Haze is a common problem when it comes to tiling and this problem seems to be on the increase due to new grout formula’s which are tougher but dry a lot faster. Usually, the excess grout can be removed using a mild acid however it is not possible to do that on Limestone as this Stone is acid sensitive and as well as etching the stone can cause it to turn white. I know Tile Doctor has resolved a few jobs like this in the past for builders who do not always understand the unique characteristics of the stone.
I discussed with the client how Tile Doctor could help and gave him a quote for the work to be carried out. He was happy to go ahead so having consulted the weather forecast for a couple of dry days we agreed a date to return.
Cleaning a Black Limestone Patio Floor
To remove the Grout Haze and clean the appearance of the Limestone I applied a Tile Doctor Brick and Patio Cleaner and worked it in with a coarse 400 grit diamond encrusted burnishing pad. The coarse pad does leave the stone looking a little rough, so the surface was then renovated using the finer burnishing pads of 800 and 1500 grit using water for lubrication. By using the pads in sequence, it gradually smooths the surface of the stone. Once done the tiles were rinsed with water and the soil removed with an industrial wet vacuum. The patio was looking good, the day was nice and bright, so we left the patio for a few hours to dry in the sun.
Sealing a Black Limestone Patio
Once the stone was dry the patio was sealed with single coat of Tile Doctor Stone Oil which is an impregnating sealer that improves strength and restores colour to the stone.
Once dry the Stone Oil was followed by a coat of Tile Doctor Colour Grow sealer which like the Stone Oil penetrates the pores of the stone improving colour and adding protection. The treatment and combination of products transformed the appearance of the patio and provided the client with exactly the look he required.
As you can see from the after pictures the patio had a rich black colour and looked as it should. The client was over the moon with the result and was thankful that we had managed to rescue his work. Lesson learned for any future project he might take on, beware of grout haze!