How to Simulate Grout Lines When Staining a Concrete Floor
- 1). Remove all the furnishings from the room where you are working. Take all photos down from the walls. If you are working with new construction, skip to step 4. It is best to score the concrete before framing the walls for ease of movement. Use a walk behind concrete saw to cut the concrete before framing the walls. Rent a walk behind saw at your local tool rental store.
- 2). Tape off the room where you are going to be working. Place plastic sheets over the walls to capture the concrete dust and help to keep the cleanup to a minimal. When you score the concrete, it makes a lot of fine dust. Use painter's tape to hang the plastic sheets. Painter's tape will not harm the wall finsih.
- 3). Layout your grout line design on the concrete. Use a pencil to make reference marks on the concrete. Snap your cut lines using a chalk line with blue chalk. Red chalk will leave a red stain on the concrete that will be visible even after staining. Make your chalk lines extends past the stop points for each cut, which makes it easier to see as you score the concrete. If the pattern dose not work properly, sweep the blue chalk, remove the design and start over, which is the most critical step to making the concrete look like grout lines. The chalk outline will provide a straight reference line that will represent the grout lines.
- 4). Cut the chalk line with a circular saw and a masonry blade. Use a straightedge to guide the saw. Straight lines are extremely important for the faux look to succeed. Set the saw to cut 1/4-inch deep only. Be particularly careful cutting the chalk lines not to go past the intersection of two lines. A 2x6 piece of lumber that is very straight works excellent for a straight edge.
- 5). Score any tight places or details using a 4 1/2-inch grinder and a masonry blade, which is small enough to get into places that the circular saw can't reach.
- 6). Grouting the score lines after the concrete has been stained and sealed with one coat of sealant will keep the grout from sticking to the concrete surface. Grout the score lines just like you would for floor tile.
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