This is a long-lasting floor mat I made for my rolling office chair. It won't dent like the cheap plastic floor mats, and it's relatively cheap to make.

This instructable shows you how I made it.

Step 1: Prepare Laminate Flooring Pieces

The cheapest box of laminate flooring I could find was about $30 USD. One box covers an area roughly 4 feet by 5.5 feet, which is perfect in front of my 6-foot work table. A smaller mat can be made by simply not using all of the boards from the box.

For this use, the cheapest laminate is the best choice not only for price, but because it is perfectly smooth. The more expensive laminate flooring styles have slight waves, gouges and mars to imitate real wood. That looks nice in a dining area, but is the opposite of what a person would want in this application.

The boards are made with a tongue-and-groove system that allows them to snap together along both the longer sides, as well as the narrow ends. Both the tongue side and the groove side have portions that extend out past the upper finished surface of the board, which are generally hidden once the boards are installed. (The groove side has a 1/2" tab that extends out from the bottom of the board that locks onto the bottom of the tongue side of the opposing board.)

For this use, however, these extending portions must be removed from any areas that will become the perimeter of the assembled mat.

I began by trimming away the bits from the narrow ends of all boards using a cross-cut sled on my table saw.

Then, along the lengths of two boards I trimmed away the tongue from one board, and the locking tab below the groove from the other. These two boards will be the end pieces on the right and left sides of the assembled mat.

See photo notes for additional details.

Step 2: Prepare Base

My initial thought was to just glue together pieces of laminate flooring and use this as a chair mat, but I quickly dismissed this idea because it just wouldn't be substantial enough. The pieces of flooring needed to be mounted onto a heavy, flat base.

The base material I chose was 3/4" particle board. Particle board is generally used as a sub-floor material in houses anyway, so it seemed ideal to use as a base for a chair mat.

Particle board has a lot going for it in this application: it is cheap, heavy, and consistently flat. This board was around $15 USD.

Based on the measurements of my trimmed laminate pieces, I determined the necessary size for the base piece and cut it out with a circular saw.

The only trick here is to make sure you do not cut it too small.

Step 3: Prepare Trim

Around the perimeter of my mat I added some trim, both to cover the raw edges of the laminate and particle board, and to act as a bumper to keep me from accidentally rolling off the edge of the mat.

The trim pieces were made from 3/4" thick alder boards, from which I cut a few 1 1/2" wide strips. I used a router to round over the two edges which will become the top when installed. I filled any cracks with putty, sanded them smooth, and then stained and sealed the pieces.

When installed, these will stick up past the height of the mat an additional 1/2".

Step 4: Install Trim

The trim pieces were measured and mitered at the corners with a homemade 45-degree sled on my table saw. A miter saw could have been used as well.

These were installed with 1 1/4" brads with a nail gun, with one of the shorter sides left off to allow for easier installation of the very last piece of laminate. A bit of wood glue was used on the bare wood at the corners of the trim pieces.

The fit wasn't exactly perfect, as you can see in photo 3, but close enough for me.

The corners were touched up with a bit of sandpaper and a quick dab of stain to cover the bare wood.

Step 5: Install Flooring Pieces

Beginning along the shorter side where the trim was installed, I began adding the flooring pieces. The first piece is the one with the tongue portion trimmed away. The trimmed-tongue side side goes against the wood trim, with the groove and locking tab side pointing toward the open area of the particle board base.

I chose to add construction adhesive underneath the pieces of laminate, rather than to let them simply "float." It took two cartridges of construction adhesive to complete the entire mat.

Only enough adhesive was applied for the installation of one board at a time. The boards snap in place with a few direct blows by either fist or rubber mallet. I just used my hands, but if I was installing a huge floor I would definitely use a mallet.

Step 6: Add Final Piece of Trim

With all the pieces of flooring in place, I added the final piece of trim and touched up as needed.

The final step is to quickly move this onto a perfectly flat surface (my garage floor is not), and walk all over it.

This will settle the boards into the adhesive and remove any slight buckles or waves that may exist. I walked around and jumped on every square inch until I could no longer hear the adhesive popping and squishing, and could no longer feel the boards settling.

I sat in my office chair and rolled around freely on my solid wooden chair mat. No more sitting in divots!