or can i just start laying it directly on top of the cement floor?
You can lay it directly on the concrete. Be sure that the concrete is flat-no peaks or valleys. That will allow the tile to sit securely and not crack. Hope this helps.
You can lay tile directly on cement floor.
I okorder and this is what I found out. Paint, cutback adhesives, gypsum based fillers or levelers, sealers, or chemically treated cement substrates are unsuitable surfaces to install ceramic tile over and should be removed by non-chemical methods whenever possible. Concrete substrates must be thoroughly cleaned prior to the installation of tile. To remove dust, mop cement slab using clean water only and allow to dry completely. Very smooth concrete may be roughened up or etched using an acid based solution designed for this purpose. Make sure to fill in and float off any dips, humps, or waves on the concrete foundation using a portland cement based floor leveler. For dips, this product may be used to fill the cavity and screed off using a level or straight edge. For humps, apply the floor leveler around the base of the protrusion. Then, using the top of the hump as a guide, screed the floor around the base of the hump in a circular motion. This will help to lessen the impact the protrusion will have on your finished floor Hope this helped, we installed ceramic tile once and had some problem and wanted to try and help if I could. Good luck with you installation..
woodtick gave you exactly the right answer,,, existing cracks in your slab WILL transfer through the tile work fairly quickly.
No. You may want to apply a waterproofing to the slab first. Make sure it is compatible with tile mastic.
