Build brick wall with mortar that lasts If you’re trying to match, patience and diligence key
stored. I talked with the masonry foreman for a short time, asking him about what they were using for both the brick and stucco restoration.
His answer was simple: “We just use hydrated lime. It can last for centuries, especially here in Puerto Rico where we don’t get freezing weather.” He did say the stucco on the front of the church did have some white Portland cement added to it to make it more durable for people touching the walls.
Matching mortar takes lots of patience. It’s important to realize that you need to match the sand in the old mortar when you’re repairing mortar or trying to match up mortar for a room addition.
Not all sand is the same.
Look very closely at a weathered mortar and you’ll see that not only are the grains of sand different sizes, but they’re also often different colors. Remember: Sand is nothing more than very tiny pieces of rock. Sand is to ants what boulders are to us!
You need to visit several nearby gravel pits that sell sand to try to locate sand that matches what’s in your current mortar. This requires diligence, determination and discipline. It will be rewarded if you find the correct sand. Use a 10X magnifier to really get a feel for what your sand looks like before you go. If you have a smartphone, snap a close-up shot of your mortar so you can see the colors and relative sizes of the grains of sand.
It would be very wise for you to take your time and do a small test panel before you install the brick on the addition. Lay up a tiny brick wall that’s maybe a foot tall by two feet long. Allow the mortar to cure. Remember that the sand particles are going to be covered with the lime paste so the mortar will dry with a uniform color and look nothing like your 100-yearold mortar.
This paste wore off your existing home’s mortar decades ago, which is why you can see the individual grains of sand now. After a month, do a very light acid wash on the test panel to dissolve the lime paste on the sand. You should be happy with the results if you invested the time to get the right sand.