Scoring
Scoring is a relatively simple technique that can add beauty and elegance to your acid stained concrete floor without a tremendous amount of additional work or cost. Some floors look great with a single large slab or only a few slabs. On the other hand, scoring can be used to break up a large slab into eye-pleasing tiles or other interesting patterns. The possibilities are only as limited as your ability to create them.
The technique will require:
-a good circular saw
- an abrasive blade for the saw
- chalk lines or other means of creating the desired pattern
- measuring tapes for pattern design
- straight edges or other means for controlling the saw cuts
- dust masks or respirators
For the example project, we decided on a simple 2 foot by 2 foot tile pattern. We felt that this would make for an interesting traditional look that would compliment the simple shape of the area.
Start the project on paper. Imagine a few different design styles that you might like and draw them out. Just remember that for some people (like me) it is really hard to visualize the pattern until its actually on the floor.
Saw setup.
Make sure you have your circular saw in order and a good abrasive blade. I like saws with the laser so I can keep track of my lines, but I never use the laser for accuracy.
Abrasive blades can be purchased at most hardware or building supply stores. We’ve found that you don’t need a very fancy one; a cheap version will probably work just fine.
Next measure the distance between one side of the saw guard and the middle of the blade. This allows you to accurately set the straight edge for scoring.
Pattern setup.
In our example, we used simple straight chalk lines for the pattern design. We just measured off of an existing division between two slabs and slapped down chalk.
Setting up the straight edge.
Once the pattern is down, you can prepare to start scoring. We have found that free-handing straight lines with an abrasive blade is essentially impossible. Using a straight edge makes for quick and accurate work.
We used a piece of tapered wood trim from another project for our straight edge. The saw side was about 1/2″ tall for the saw guard to slide against and the opposite side was more narrow for the weights to sit on. Really any straight and fairly narrow material can work. We used cinder blocks as weights, but you could use pretty much anything heavy. The sealant cans work well and are easy to move.
Remember the measurement from the blade to the saw guard? That will be the distance between the straight edge and the chalk line. Measure twice, cut once. Mistakes in concrete are mistakes for life.
Scoring the concrete.
Proper safety equipment is critical to your health! Abrading concrete makes more dust that you would ever guess and the dust is dangerous! Dust masks, protective glasses, gloves and good clothing are recommended. This does not consitute proper safety equipment!
The depth of the abrasive blade depends on the flatness of the slab and the desired effect in the concrete. We recommend setting the blade not much more than 1/8″ to 3/16″ on level floors. Trial and error in a hidden section of the floor is highly recommended.
You will also find that a traditional circular saw cannot cut all the way up to a wall. We compensated for that by scoring a line 6″ from all walls as a solid tile boundary and stopping the interior lines at that line. We have also done projects without the “perimeter” line. Both styles look good. Note the scoring pattern in the picture below.
Once you have the pattern laid out and the straight edge set (measure twice or more!) then you are ready to cut.
Expect a lot of dust.
A good line coming through.
This is a picture for the Porosity Test, but it shows the finished pattern well.
Clean up.
Concrete dust is very light and will stay in the air quite awhile. Proper room clean up is important. Good ventilation will speed the process as it will take concrete dust out of the air. By good ventilation I mean light air movement, not a commercial fan!
Next: Floor preparation.