How to Install Carpet Tiles Over Concrete

Carpet tiles -- also known as carpet squares -- provide a convenient way for do-it-yourselfers to add the comfort of carpet to their floors without the work that traditional wall-to-wall carpeting entails. When they become stained or otherwise damaged, you can swap them out for new tiles without having to replace the entire floor. Carpet tiles are suitable for almost any existing hard floor surface; they offer a distinctive option for a finished basement with a concrete floor.

Finished Basement with Stone Fireplace
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How to Install Carpet Tiles Over Concrete

Check for Excess Moisture

Carpet tiles on concrete rely on adhesive to stay in place; conduct a moisture test before you purchase and install your tiles, as damp concrete will prevent the carpet tile glue from adhering. You can buy a concrete moisture <atarget="_blank" href=""> </atarget="_blank">test kit at hardware or home improvement stores. If the test reveals that you have a moisture problem, you will need to seal the concrete and allow it to cure for 90 days before going forward with your carpet tile installation.

Carpet Tile Installation

Installing carpet squares over concrete is a simple process requiring only a few basic tools. You should be able to finish your project in less than a day, depending on the square footage you need to install.

Measure the room's length and width and then multiply the two to arrive at the room's square footage. For a complex room shape, divide the room into smaller rectangular sections and add their areas together. Purchase enough carpet tiles to cover the entire floor.

Clean the Floor

Sweep or vacuum any dust and debris to make a clean work surface. Use a chalk line to snap perpendicular lines from the center point of two adjacent walls. When complete, the lines should cross in the center of the room.

Purchase ten percent more carpet tiles than you need in the event you make a mistake while cutting, or to replace damaged tiles in the future.

Test Carpet Layout

Temporarily place carpet tiles along the chalk lines in the center of the room to test the layout and the pattern. Place a corner of the first tile at the intersection of the chalk lines, then place adjacent tiles horizontally and vertically along the chalk lines starting at the center tile. If any remaining spaces along the walls are less than 4-inches wide, adjust the layout and snap new chalk lines to create one larger gap and reduce the amount of cutting.

Install the Tiles

Begin at the center of the room and install the carpet tiles along the chalk guidelines; these will be the baseline tiles. Peel the backing from the adhesive strips on the backs of the tiles, and press into place, aligning them carefully as you work. The tiles should fit tightly together with no gaps. Once the baseline tiles are in place across the length and width of the room, fill in each quadrant with additional carpet tiles.

Fill in the Gaps

Measure the remaining areas along the wall to know the size to cut the carpet squares to fit. Use a marker and a framing guide to mark the backs of the carpet tiles according to your measurements. Use a carpet knife to cut the tiles to size, and then install them in place.

Cut Complex Shapes

Create templates on paper to help cut out complex shapes, like around door frames or cabinet bottoms. Make a sketch of the shape, then measure all of its dimensions and note them on the sketch. Use a framing square to create an accurate copy of the shape on heavyweight paper based on your dimensions. Cut out the template, turn it over and place it on the back of a carpet tile. Trace around the shape with a marker, and then use a carpet knife to cut the tile.

To save money, time and effort, you can install carpet tiles as an area rug, using only whole tiles and leaving some of the concrete floor exposed.

Jennifer Roberts

Jennifer Roberts has enjoyed writing since 2008. Her professional experience includes computer aided drafting and design in the hospitality industry, graphic design for several nationally televised PGA Tour events, and an adjunct professorship in Computer Aided Design. She holds a Bachelor of Science in architecture from the University at Buffalo.