How to Make Concrete Fascia Stones

You can create the look of a real stone wall by casting your own concrete fascia stones.

You can make an existing wall look like it's built of stone by using concrete fascia stones. Fascia stones install much like wall tile, except that you have much more freedom in how each stone is placed. Using the right concrete molds and the coloring of your choice, you can create almost any look you can imagine, from smooth river stones to chiseled sandstone blocks. Making your own fascia stones takes extra time, of course, but it can also save you a lot of money over buying precast fascia stones.

Things You'll Need

• 20 gallon bucket
• 2 1/2 gallons water
• Concrete colorant
• 47 pounds Portland cement
• 1 5-gallon bucket sand
• 2 5-gallon buckets lightweight aggregate (such as Perlite)
• Latex rock face mold
• Stick or nail
• Plastic wrap

Instructions

1. Pour water into a 20 gallon bucket.

2. Add concrete colorant to the water and mix well.

3. Add half of the Portland cement.

4. Add the sand.

5. Add the rest of the Portland cement, and mix well. Mix should be wet and soupy at this point; if it's too stiff, add a little additional water.

6. Add one bucket of the aggregate, and mix until until the aggregate is completely covered with concrete.

7. Add the second bucket of aggregate, mixing it to cover it with concrete. Add more water if the mix becomes too stiff to work. The final mix should be the consistency of a thick batter.

8. Pour the concrete into the rock molds.

9. Bounce and shake the molds on a flat, level surface for about 20 seconds, or until the concrete in the molds levels out.

10. Etch horizontal lines across the top of the concrete using a stick or nail.

11. Cover the rock molds with plastic wrap.

12. Allow the concrete to set for 24 hours.

13. Remove the stones from the molds and wrap them again in plastic wrap.

14. Store the wrapped stones in a sheltered area for two to four weeks to allow the concrete to finish curing.

Tips & Warnings

• Check with the mold manufacturer to find out how much concrete it takes to fill the mold you're using. You may need to buy more molds or reduce the concrete recipe so you don't have a lot of concrete left over.

• Many lightweight aggregates absorb a lot of water, so be sure to have more on hand when you're adding the aggregate to the concrete.

• You can use a cement mixer if you need to make large batches of concrete.

• If you're using a vibrating table to vibrate the filled molds, reduce the vibration time to 10 seconds.

• If you're planning on covering a corner with concrete fascia stones, you may need to purchase an additional corner mold.

• Concrete fascia stones can add a great deal of weight to your wall. Be certain your wall can bear the weight of the stones before you start the project.

• Do not use regular concrete aggregates or gravel in your concrete mix; the stones will be too heavy to use as fascia stones.

• Do not over-vibrate the filled molds; this can weaken the stones or give them a striped appearance.

• Failure to allow the finished stones to cure for at least two weeks can seriously weaken the stones.

References

• The Mold Store: How To Guide to Making Lightweight Concrete Formulas
• Mold Creations: Mold Instructions
• Mold Creations: Recipes for Concrete, Lightweight Concrete and Hypertufa

Resources

• Working with Concrete Molds
• Mold Warehouse: The use and care of ABS concrete molds