One of the greatest advantages of the DIY Peel & Stick Backsplash tiles is the ability to install them over existing tiles. However, you need to pay attention to a few things:
1) The existing tiles have to be firm on the wall. If they are coming off the wall, you will need to remove them before installing the peel and stick mosaic tiles;
2) Make sure the surface is clean - free of oil and dust.
If your backsplash meets the above, go ahead and plan your installation.