Q: We recently bought an older house, which has dingy linoleum flooring glued down around the perimeter but unglued in the center. We would like to update this flooring with vinyl, either tiles or sheet vinyl. Can we install the new flooring over the old? Any advice you have would be appreciated, as this is my first attempt at laying a floor.

A: Since the linoleum is not firmly attached to the subfloor, it should be removed. However, an older flooring such as yours should be tested for asbestos before removal. If the flooring contains asbestos, a licensed asbestos remover is required to do the work in most states. Another option would be to encapsulate the asbestos flooring by putting down an underlayment over the existing linoleum.

An underlayment may be required even if you remove the linoleum. The surface to which you are attaching the new flooring should be perfectly flat and smooth. A wood floor in good condition that has a subfloor underneath is suitable. Otherwise, you should first cover the floor with quarter-inch-thick plywood or hardboard underlayment, available at lumberyards and home centers. Smooth plywood is best because of its durability, but untempered hardboard is less expensive and will last as long as most resilient tiles. Because hardboard readily absorbs water, do not use it in such places as kitchens and bathrooms.

Acclimate the underlayment material to the temperature and humidity of the room by standing it on edge for at least two days in the room where you intend to install it. To secure the underlayment, you will need lots of ring-shank flooring nails. Drive in one every four inches across the sheets into joists. Stagger the sheet joints, beginning in the center of the room and arranging 4-by-4 or 4-by-8 panels so that four corners never meet. Space the panels about 1/32 inch apart--the thickness of a dime--to allow for expansion without buckling.

Resilient vinyl flooring can be installed on any grade, making it suitable for installation directly on concrete slabs--except in some cases flooring will not be suitable for installation on concrete in contact with the ground because of migrating moisture problems.

When purchasing resilient flooring, you can choose from several grades and price ranges. Better grades are very durable, resistant to abrasion and discoloration. Cushioned vinyl is soft underfoot, has a minimum of dirt-catching seams and comes in rolls up to 12 feet wide. Sheet vinyl is difficult to install and in most cases should be laid by professionals. Installation kits for do-it-yourselfers are available, but remember, a cutting mistake can ruin an entire roll, not just one tile.

For most do-it-yourselfers, the vinyl tiles are a better bet, less expensive and easier to install, with a wide selection of patterns and textures readily available. Many come with an adhesive backing, making them even easier to set. Most tiles come with instructions.

The first and most difficult step is laying out the tile positions on the floor. If the room is square or rectangular, start by snapping chalk lines between the midpoints of the walls so the lines make a right angle in the center of the room. Position a row of tiles--without adhesive--along the chalk lines starting from the center and creating an L extending from the center toward two sides of the room.

If the space between the last tile and the wall is less than half a tile wide, move the row toward the opposite wall a distance of half a tile. This avoids having to trim any tiles to less than half their width, which weakens them. Adjust the chalk lines accordingly if you move the tiles.

Lay a second row of tiles along the chalk lines, stretching to the remaining two walls. You may have to make another adjustment if the last tiles are less than half a tile wide--moving both rows of tile as a unit half a tile width toward one wall and re-marking the chalk lines.

When laying out an L-shaped room, it is best to treat the space as two rectangles, making adjustments at the right angle of the room to keep full tiles in the center and any tiles requiring trimming around the perimeter of the room.

In dealing with an L-shaped room or an irregularly shaped room, or when laying the tiles in a diagonal pattern, it is often best to make a scale drawing of the room on graph paper and experiment with the layouts drawn onto tracing paper placed on top. When you choose a layout, mark it onto the floor with chalked strings. Exact planning prior to setting the tiles is essential to a successful project.

When you are ready to lay the tiles, peel off the paper backing and carefully position the tile, kneeling on it to apply pressure. If the tile you choose does not have an adhesive backing, buy a brush-on adhesive recommended by the manufacturer. Follow instructions printed on the adhesive container. Lay full-size tiles in the areas aligned with the chalked lines, working one-quarter of the room at a time. Set the border tiles around the perimeter last.

To trim a border tile, put it on top of the tile it will rest against. Place a second tile over it and slide the second tile to the wall. Using a sharp utility knife, score the border tile by using the overlapping edge of the top tile as a straight edge. Then cut or break the border tile along the line. The exposed portion should fit the space. Do corners in a similar fashion: Place a corner tile over the last tile on one side of the corner; mark with a pencil. Repeat on last tile on the other side. Cut along marked lines where they intersect.

Send e-mail to copleysd@copleynews.com or write to Here's How, Copley News Service, P.O. Box 120190, San Diego, Calif. 92112-0190. Only questions of general interest can be answered in the column.