Homework: How to tuck-point brick

Water, snow and ice erode both brick and mortar. Perhaps the most damaging of the three is ice. Water that soaks into the mortar between brick can and does freeze. Water expands as it freezes and this expansion causes the tiny sand and cement paste particles to detach and fall away.

It takes years for this to happen, but over time you'll see mortar joints that are crumbling, more recessed than you remember them to be years ago and softer.

It's not too late to tuck-point your brick -- or fill eroded mortar joints with fresh mortar -- before the bitter temperatures brought by Old Man Winter settle in. The best part is that it takes a minimum of tools and supplies to tuck-point brick. Only attempt this job if the air temperature will not drop below 32 degrees for at least 48 hours after you place the new mortar.

STEP 1

Go to the most remote part of your house, that place you rarely look at, to begin this job. You want to make any mistakes here, not near your front door. Use a narrow cold chisel and a hammer to tap out any loose mortar, being careful not to chip the brick. Wear safety glasses, work gloves and work slowly. Brush out all loose mortar and remove all dust.

STEP 2

Where the existing mortar is still in good shape, take a very close look at it. Use a standard 4-inch magnifying glass. You'll quickly notice the mortar is made up of tiny grains of sand of different colors. You may have red, orange, black, gray and brown sand grains in the mortar. Try to determine a rough percentage of each color. Pay attention to the color of the mortar paste between each of the sand particles.

STEP 3

Visit a local gravel pit that sells sand to bricklayers. If you don't know where this is, visit a brickyard and ask them. You want to get several five-gallon buckets of clean sand that's not only the same size sand particle as is in your mortar, but also as close to the colors of the sand as possible. This step is the most important if you want your tuck-pointing work to match your existing mortar as closely as possible.

STEP 4

Purchase a bag of brick mortar mix from the brickyard. Look at the sample color charts they have and get one as close as possible to your mortar color. Remember, here you're just trying to match the color of the mortar paste between each of the sand grains in your mortar.

STEP 5

Gather the needed tools to install the new mortar. You'll need a regular V-shaped mortar trowel, a narrow 3 / 16-inch tuck-pointing trowel and some sort of jointing tool. Most mortar joints have some type of profile that was given to them while the mortar was still wet when your house was built. You want to match this profile and the brickyard store will sell all sorts of different jointing tools.

STEP 6

It's time to mix the mortar. Mix two parts of the sand to one part of the powdered mortar. Do not purchase premade mortar mix from a home center. This is for new work and it will not match. Don't fall into this trap. Blend the sand and mortar dry and then add enough water so the mix resembles a not-so-wet applesauce. You want it wet, but not so wet it runs off the trowel.

STEP 7

Take a stiff brush and brush away any loose mortar from where you're going to tuck-point. You want the area dust-free. Spritz the mortar joint with a fine mist of water using an old spray bottle. Don't get the brick and mortar joint too wet.

STEP 8

Get some mortar on the V-shaped trowel and hold it next to a horizontal mortar joint that needs to be filled. Use the narrow tuck-pointing trowel to push the mortar into the joint so it's completely flush with the face of the brick. Wait about 15 minutes and use the jointing tool to smooth the mortar so it matches the existing.

SUMMARY It takes some practice to not smear the mortar all over the brick. Take your time as it's very hard to clean the mortar from the brick. Next spring wash the tuck-pointed mortar joints with a muriatic acid solution -- one part acid to 10 parts water -- to wash off the mortar paste from the sand. Rinse with clear water. Once dry, your new mortar should match the old very well if you got the right sand and powdered mortar.

DEGREE OF DIFFICULTY

3 hammers out of five

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