How To Tuck-Point Mortar On A Brick Porch

by Darwin Hall

tuck-pointed brick porch

Tuck-pointing brick or concrete blocks can be a tedious, messy job.  Over time, mortar will deteriorate, especially in freeze-thaw states around the U.S.

I had a porch tuck-pointing job on a old house in Detroit.  Both sides of the steps leading up to the front door are original brick stoops (or sitting pads), which needed attention.

The foundation is brick, too — with a weave pattern interwoven into the stoop.  Many years ago, the homeowner said they had the front steps poured with new concrete.

The contractor who poured the steps ended up dislodging one side of the left stoop closest to the driveway.  Over time, the mortar was further damaged by moisture entering into gaps of the dislodged area, and created a situation where the bricks were eventually going to fall.

See also:  Working With Mortar

So I headed out to the property, but before I went to the job, I stopped by the local home store to get a few supplies.  There are many kinds of mortar and concrete to choose from in the concrete supply isle, as well as base sand and tools.  For this project, I needed to get a strong mortar mix, specifically for tuck-pointing.

After grabbing a couple of tools and the bag of mortar, I headed to the jobsite.

Step 1

The first thing I do is assess how much of the old mortar that will need to be removed.  If you have a small area to tuck-point, you can chip the mortar away with a ¼-inch-wide cold-chisel and a hammer.

I take a look at the other joints.  Mortar that needs to be removed will be loose, powdery, and crumbles easily.  For a project like this, I like to use a combination of things:  the chisel, hammer, and power grinder — to get a thorough cleaning of the brick.

before tuck-pointing porch 4 side view

before tuck-pointing porch 2 front view

before tuck-pointing porch 2 side view

before tuck-pointing porch 1

I moved the cap stone out of the way and proceeded to use a rubber mallet to tap some of the loose bricks back into the wall.  Once satisfied with the flatness of the porch wall, I began by striking several pieces of loose mortar with the chisel at a slight angle just beyond the edge of a brick.

For wiggling vertical chunks, pry the pieces out starting at the top of a course.  You should move on to using an angle grinder when you can’t remove any more mortar with the hammer and chisel.

For large areas, you can use the grinder with a 4-inch diamond cutting wheel.  Using this tool is very efficient and speeds up the process.  It also creates a lot of dust, so make sure you wear a dust mask.  Choose a good mask; a standard painting mask may not work — it will allow dust to get in through gaps at the sides.

You should pick a mask that covers the nose and mouth with a rubber gasket, has breathing filters, and is approved for this kind of work.

Begin by grinding mortar away from horizontal joints.  As you grind the joints, you’ll feel how far to go back past the damaged areas, because the wheel will slow a little, and not cut through the mortar as fast and as well as before.

For vertical joints, plunge-cut them with the grinder, being extra-careful not to go too deep, or else you’ll damage the bricks above and below the cut.  If you notice red dust as you’re grinding mortar, you’ve started cutting into the brick.  Simply adjust your technique accordingly.

Step 2

Prepare to mix the mortar.  I used a type S professional grade mortar from Quikrete, sold in an 80 pound bag.  It is a very strong bonding material for tuck-pointing old brick.

quikrete type s mason mixThe bag is pretty heavy; you should use a dolly-style cart commonly found in most home stores, so you won’t have to lift it up too high.

Fill a small bucket with one quarter full of cool water.  While stirring, slowly add the dry mortar to it.

You don’t want to do this process vice-versa (adding water to the powder); because you won’t be able to fully stir and mix the powder at the bottom of the pail.

You also won’t be able to accurately gauge how much of each ingredient to mix together.

As you’re mixing, the mix should not be runny.  For clumps in the mix, simply cut through them with your brick trowel and continue stirring.  Use a 1 x 2 -inch piece of wood, about 2 to 3 feet long to stir the mix if it becomes hard to turn.

At this point, you should test the mix by putting some on your brick trowel.  Hold it at a slight angle to see if the mix falls off.  If a lot of it does, add a handful of more dry powder to the mortar.  The mix should have a consistency of oatmeal.  It also has a certain sound as you stir, letting you know it is ready.  Let it sit for 10 minutes before you start filling joints.

Step 3

While it’s sitting, fill another bucket half-full with clean water.  Dip a hand-held broom in it and coat the outside of the brick area horizontally with the clean water.  This allows the bricks to not soak up the mortar mix too fast and cure, causing cracks.  It also helps the mix to stick to the joints better.

Start applying the mortar to the horizontal joints.  With one hand, hold a fair amount of mortar on your brick trowel directly under a joint.  With the other hand, slide mortar off the trowel and into the joint with your tuck-pointing tool.  Buy one that’s about ¼-inch thick.

While working, try to limit the amount of mortar mix sliding off the backside of the trowel and onto the ground, by holding the trowel at a very slight angle toward the brick.

As you finish loading the joints with mortar, use the trowel’s blade to scrape the brick face of extra residue.  Keep moving along until all the horizontal joints are filled.

Next, do the vertical joints.  As with before, hold the trowel in one hand.  But this time, hold the tuck-pointer vertically and slide mortar mix in.  Scrape off any outside residue using the trowel’s side in a diagonal motion going up or down.

Step 4

For mortar mix that fell to the ground, simply scrape it into a pile with your brick trowel.  The dust on the ground created with the grinder will also allow the wasted mortar to be coated with it, making clean-up easy.  Scrape the stuff up in a few piles while the mortar in the joints are drying.

After a while, use a hand brush to clean the brick face, removing additional residue off before it gets a chance to dry.  You can tool the joints when the mortar has set a little.  As the mortar dries, fill any areas that need it with another layer of fresh mortar to give the overall project uniformity and evenness.

Touch the mortar to determine if it is time to finish it — your finger should leave a slight impression in it.  Follow the horizontal path of the joints with different ends of the joint finishing tool as needed, making several passes to get a smooth joint surface.  Then do the smaller, vertical joints.  Brush the bricks down with the square brush again, in between steps as needed.

tuck-pointed brick porch

tuck-pointed brick porch

A good idea is to clean-up the floor area while waiting to finish different sections of joints.  It’s better to gather all the splotches of mortar now than to wait — because of course, they will be more difficult to remove when they have dried.

Immediately after smoothing all joints, wash off any mortar from your tools.  You can use an inconspicuous area to clean out the buckets and dump the water.  If you didn’t get the brick face clean from excess mortar to your liking, you can use muriatic acid — but wait a few days to remove the stuff.  Be careful and follow the manufacturer’s instructions.

Step 5

The next day I re-installed the cap stone to the porch wall.  I grinded and chipped the top of the bricks until most of the old mortar was removed.  I then mixed up a new batch of mortar, wet the bricks with plain water, and liberally spread the stuff along the top.

With help, I carefully laid the cap stone into place.  You only have a few moments to re-adjust it’s position before the bed of mortar locks the cap stone into place.  Once it was set, I tuck-pointed the top joints of the brick underneath as I did with all the other joints.  Other cracks in the new mortar that surfaced from the day before were filled too.

Tools You’ll Need:



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