In most cases not a good idea. What is your current flooring now?
It is a surround of a fireplace
If it is a vinyl tile you can tile over it. If ceramic or porcelain you cannot.
think you have to take the old tile off. How about stenciling it to get a new look.
how about stenciling it for a new look?
Most cases I've seen, Mary, people have removed the old tile before putting on the new. There are several reasons for this. One is the added weight from putting tile on top of tile. This could cause the surround to fail and fall apart. The adhesive also may not adhere to the old tile well and all of your work could end up on your floor. I'd say just go for it and do it right the first time. Old tile can be removed using hammers and chisels. Please let us know what you've decided to do!
For ceramic you can tile large format tile over small format tile. Any other tile will need to be removed. You need a solid and smooth base for tile. You can use peel and stick vinyl planks over vinyl as long as it is stable.
Mary, I agree with Naomi. Can you just take the existing tile off and put up what you prefer?