Q: A neighbor has given me a stack of bricks from his backyard. I intend to use them in the median strip between the curb and the sidewalk in front of my house. Many of the bricks have old mortar stuck to their sides that I need to get rid of. Can you recommend an alternative to the chisel-and-hammer method suggested at my local hardware store? Also, if the bricks can’t be cleaned up, how do I dispose of them?
A: It’s great that you’re preparing a new home for those old bricks. Not only do we prefer the look of used brick to new, we like the fact that you are reusing perfectly good material.
You have a good deal of work ahead of you, but take heart — it’s not difficult, just time-consuming. Also, you probably won’t be able to salvage all your neighbor’s used bricks. Inevitably, a few will be beyond redemption or will break apart when you remove the mortar.
Your first step should be to soak the bricks in a solution of muriatic acid and water. This will soften the cured mortar enough to allow removal via the tried-and-true method of hammer and cold chisel. The alternative, and our preferred method, is to saw the mortar off using a diamond-encrusted blade fitted to a circular saw. Kevin’s father-in-law, Ed, a master mason, used this method to dry cut bricks when doing small jobs.
Masons have used muriatic acid, also known as hydrochloric acid, for years to clean mortar residue from brick and stone. At the end of any job there’s a residual gray film from mortar on the bricks. Muriatic acid emulsifies the Portland cement contained in the mortar allowing for easy cleanup. It is not used full strength but is diluted with water, usually 10 parts water to 1 part acid. Directions for dilution and safe handling are printed on the label.
Be warned: Muriatic acid is quite strong, and it’s dangerous when it comes in contact with skin or mucous membranes. So it is critical that you take proper safety precautions. Suit up with rubber gloves, long pants, a long-sleeve shirt, a hat and eye protection. If the solution gets on your skin or heaven forbid in your eyes, immediately flush the area with cold water. For more tips on working with muriatic acid, click here.
To do the job, first prepare a work area. Lay out a heavy canvas or plastic drop cloth to stop any acid solution from seeping into the ground. Set up a bench or table (a piece of 3/4-inch plywood and a couple of sawhorses will do).
Next, lay out your tools. If you opt for the power saw, make sure to use one that’s light enough for you to handle comfortably for long periods of time. Also use a GFCI-protected (ground-fault circuit interrupter) outlet for a power source. You’ll be working around water, and this will prevent electrical shock.
Mix the acid solution according to the manufacturer’s instructions in a 5-gallon plastic bucket. To prevent possible eruption or spillover, always put the water in first, then the acid. Fill the bucket about half full and drop in as many bricks as it will hold without overflowing. Make sure the bricks are totally submersed.
Let them soak for about 15 minutes then pull them out of the bucket and place them on your worktable. Put more bricks in the bucket to soak while you clean the soaked bricks.
Chip, chisel or saw the old mortar off the soaked bricks. Once you’ve got most of the mortar off, get rid of the residual mortar by giving the bricks a good scrubbing with a wire brush. Stack the cleaned bricks in a pile and repeat the process. Before you know it, you’ll have all the salvaged bricks cleaned and ready for their new home.
If for some reason you decide you can’t use them or just don’t want to tackle the job, you can easily sell them or give them away. We’d bet an ad on Craigslist would have them gone in less than a day.