It is possible to cover your linoleum tile without removing the old linoleum. Depending on what you plan to lay over the old linoleum you may or may not need to put down what is called an “underlayment” over the old linoleum. Not only is it possible to cover linoleum tile without removing the old tile, it's often preferable, particularly in older homes where the linoleum may contain asbestos.
Underlayment is not a subfloor, although some do-it-yourselfer's often mistake it for that. It can be anything from particle board, hardboard, OSB (Oriented Strand Board), or plywood. Underlayment is the level in-between the sub-floor, which is the structural level of the floor, and the actual flooring material, which may be carpet, tile or wood. It's important to select the correct type of underlayment for the type of flooring you plan to install. Different floorings, such as tile and wood, need a different underlayment than carpet or linoleum.
Things to Consider when Covering over Linoleum Tile
Although underlayment is thin, by the time you add your new linoleum, tile or wood floor you may actually raise the level of your floor as much as 3/4 inch to 1 inch. This won't matter unless you have kitchen appliances, storage bins or other items that may be affected by raising the floor level.
If you have a linoleum floor installed before 1978 you will be encapsulating what is most likely linoleum with asbestos in it. This is a good thing.
Using underlayment will make your new linoleum floor smoother than simply laying new linoleum over the old.
It is less expensive to lay a new floor over existing linoleum rather than to remove it.
It is possible to lay carpet, wood, ceramic or stone tile, rubber or paint over an existing linoleum floor.
What You Can Lay over Existing Linoleum
Carpet - Carpet and carpet pads can be laid over existing linoleum by doing nothing more than cleaning the linoleum before installing the pad and carpet.
Wood Floors - Wood flooring is nailed directly into the sub-floor or linoleum so no removal is necessary. Simply clean and install the padding if installing a floating floor, or just nail the flooring directly into the linoleum.
Linoleum - If you plan to install another linoleum floor over the existing floor, it's better to install an underlayment in order to keep “ghosting” of the old linoleum bumps, nicks and edges from imprinting on the new linoleum.
Tile - If laying ceramic tile, slate or stone you'll need to clean, then sand or scratch up the old linoleum to provide a surface the mortar for the tile will adhere to. Not only that, the floor must be perfectly level or the tile will crack when it is walked on. To ensure a level floor put down underlayment when laying a tile floor over linoleum.
Paint - If painting linoleum tile to cover it up you will need to clean it, sand it and prime it before applying an oil-based primer and exterior floor and porch paint.