by Bill Phillips
We've all seen brick repairs where the new mortar and brick
didn't match the original — they're visible from half a
block away. Yet with a little extra effort, you can make a
brick repair blend in so that it's almost unnoticeable. In 20
years as a residential contractor, I've picked up tips from
many masons. Recently, I started making small repairs myself
since it's often difficult to schedule a mason for a small job.
In this article, I'll explain some of the tricks I use to make
brick repairs disappear.
1. A vertical crack in the brick veneer is often
the result of minor settlement in the foundation.
Though these cracks typically stop moving and cause no
structural problems, most homeowners like them
Homeowners get very concerned when they see cracks running
through several courses of the brick veneer on their house.
Often these cracks are the result of minor settling of the
footing below ground level, but even slight settling can open
disturbing cracks 12 to 14 feet above grade. I won't try to
deal with all the possible reasons brick cracks. Let's just say
that before making a repair, I make sure that the settling was
a one-time event and that the footing or brick ledge is
Remedial work at the ground level can include regrading for
positive drainage, excavating to add or improve upon existing
drain tiles and foundation waterproofing, and in the most
extreme situations digging below an existing footing to pour a
wider base of concrete on stable ground. For very small
cosmetic cracks that have remained stable for a number of
years, simple drainage work can suffice; for larger cracks that
show considerable movement, digging down to firm ground and
adding concrete may be necessary.
Once I'm satisfied that the base the brick sits on is
secure, the repair can begin.
2. Using an angle grinder, the author scores the
mortar joints and cuts the bricks to be removed into
small sections. He finishes the removal process with
drill bits and cold chisels.
Slow and Steady
So how do you get those cracked bricks out without busting
every other brick around them? Very carefully. After breaking a
few too many perfectly fine bricks in trying to get out the
damaged ones, I came to the conclusion that slower was better,
and that removing very small pieces was the answer.
I now use a small diamond blade on a grinder to score the
brick and mortar into small divisions. After the blade has gone
as deep as it can — a little over an inch — I start
chipping out the pieces with various-sized cold chisels and
hammers. Sometimes the small 1/4-inch chisel and the two-pound
hammer work; at other times, I may use a wider 1- or 2-inch
chisel when I'm unlikely to crack surrounding brick.
After chipping out the front side of the brick and mortar,
to a depth of about 11/2 inches, I take small (1/4 to 3/8 inch)
carbide masonry bits and drill the rest of the brick full of
holes — a lot of holes. This is no fun without
good-quality bits and a good hammer drill. (I've had a Bosch
Hornet hammer drill for about 15 years — it just won't
quit.) I clean out the pieces — including, inevitably, a
couple of good bricks that I accidentally break — then
brush away the dust. Dust mask and goggles are a given for this
work. The removal of the damaged bricks pictured here took
about five hours.
3. Working slowly, the author removes the
cracked bricks without damaging nearby bricks.
Making the Match
Before beginning such a repair, I always find a matching brick
and experiment with mortar color. If the house is not too old,
a brick salesman can often identify the exact brick that was
used. With luck, it is still being made and you can pick the
few bricks you need from an open cube in the brick yard. I
always get extras for experimenting with mortar samples.
It's a little more difficult to match old brick, but usually
a solution can be found. Some older coal-fired brick has rich,
dark flashes in it, which the newer gas-and-sawdust firing
process will not duplicate. Some demolition companies store old
brick and can be a useful source. Another solution is to remove
bricks from inconspicuous places (even below grade) and blend
in the old ones with the closest matching new ones you can
Matching mortar is crucial, and a little extra care makes all
the difference between a repair that disappears and one that
shouts out at you. I keep on hand a bag of white mortar mix, a
couple of different brands of gray mix, and a tan-colored mix.
I also use black mortar tint to dull the color of the new
mortar if it looks too bright. Finally, I keep both orange sand
and white sand for the difference it can make in shading the
color of the mortar.
4. A variety of ingredients make it possible to
match existing mortar: white, tan, and gray mortar
mixes, black mortar tint to darken the mix if needed,
and white and orange sand. Shown in the foreground are
some drying samples.
Matching mortar color takes time, of course, which can make
the repair expensive. But because cracked brick makes potential
homebuyers just as nervous as finding rotten wood or standing
water in the basement, I've found that a careful explanation
usually convinces the customer of the need. Though I give very
educated estimates, I typically do the work on a time and
materials basis. I sleep better that way, but usually come
pretty close to the estimate.
As I mix the
mortar color samples, I keep written notes of the exact
proportions of each coloring ingredient in each mixture. It
works well to lay two or three bricks with each sample and let
them cure for a few days. I do all of this before tackling the
strenuous job of removing the broken brick. As any mason knows,
the same mortar sample can cure in several different shades
depending on temperature, humidity, and exposure to direct hot
sun. And mortar can look very different eight weeks after it is
mixed than it does three or four days after.
Still, a decent match can be made even though there isn't
time to wait a month for the samples to cure. I usually throw a
few globs of mortar on a piece of plywood and set them in the
sun to get an idea of the lightest possible shade at which the
mortar could cure.
The Easy Part
Laying the new brick with the matching mortar is, of course,
the easiest part of the job. Pack it in good, point it up well,
and tool it the same as the original brick. I try to keep the
brick as clean as possible while I'm laying it, using a brush
and rag to clear away excess mortar. I always go back the next
day and clean it off with water. Usually, I don't need to clean
with acid after this, but if I do, I give it a few more days,
then use as little acid as possible and rinse it well. Since
acid can weaken mortar, the extra few days gives the mortar
more curing time. Typically, a careful, quick cleaning with
diluted acid and a stiff brush will removes any small smears
and nubs without weakening the surface of the mortar in the
5. After achieving a mortar match, actually
laying the brick is easy. The author is careful to
match the pointing technique of the original work.
For a while — a day or two in the summer, a week in
the winter — the new mortar remains darker than the
surrounding mortar. Within a couple of weeks, though, it
eventually blends in with the rest of the wall. It's always
gratifying to have made the extra effort.
Bill Phillipsis a builder and remodeler in Durham,