The steps you should follow to repair racked-down
corners are as follows:
1. First remove all the bricks inside the V,
including any bricks that have been broken (fig. 7-5).
This forms irregular sides and helps to hold or key the
brick in place.
2. After the bricks are removed, clean the sound
bricks and obtain as many new matching ones needed
to fill the opening. Relay the bricks in mortar up to and
even with the horizontal crack running along the side
and end of the building. If all joints are made the same
width as the original joints and the mortar tends to match
the old mortar, a very presentable job will result. As the
bricks are built up, coat the backup bricks with mortar
so that the newly laid bricks will be bonded to them.
3. Partly fill the top joint with mortar that is on line
with the horizontal crack. This can be done by pushing
the mortar into the joint with a narrow pointing trowel.
When about half the depth of the joint is filled, fill the
remainder with sealing compound. This system of
mortaring only half the joint supports the brick above
but forms a weak plane along the top of the racked-down
areas. If movement takes place, the mortar joint breaks,
but the relaid bricks remain in place. The sealing
compound keeps the joint watertight.
INTERIOR WALLS, PARTITIONS,
Interior walls are usually made up of gypsum and
plaster materialsthe most common material being
drywall. Other materials used are plywood, wood
paneling, ceramic tile, or glazed-faced masonry.
Partitions may be of plywood, drywall, hard-pressed
fiberboard (particle board), structural clay tile,
gypsum block, metal, and glass. Ceilings are usually
Figure 7-5.Damaged brick removal.
made up of either drywall or acoustical materials.
Another material commonly used to cover ceilings is
plaster. Some of the major defects to look for when
inspecting the more common types of interior walls,
partitions, and ceilings are given in the following
Cracks, holes, and looseness in plastered surfaces
are signs of excessive internal or external stresses.
They may be caused by poor workmanship, such as
improper proportions or application of the plaster,
imperfect lathing, and poor atmospheric conditions
during plastering; by moisture infiltration or an excess
of moist air generated inside a building; or by the
settling or other movement of some part of the building
frame. External stresses that cause plaster damage
should be investigated and corrected before repairs are
made to the plastered surfaces themselves.
STRUCTURAL CRACKS are easily identified
because they are usually large and well-defined,
extending across the surface and entirely through the
plaster. They generally develop during the first year
after completion of construction and, in most cases,
can be successfully and permanently repaired.
However, before repairs are initiated, the cause of the
failure should be determined from an engineering
standpoint and necessary precautions taken to prevent
recurrence of the failure. Structural cracks may extend
diagonally from the corners of door and window
openings, run vertically in corners where walls join,
run horizontally along the junction of walls and
ceilings, or occur in walls where two unlike materials
To repair a structural crack, use a linoleum knife
or chisel to cut out and remove loose material. The
crack must be formed to a V-shape to provide adequate
keying action by making the surface opening narrower
than the bottom of the crack. Care should be exercised
to widen the crack only enough to ensure a good bond
between patching plaster, old plaster, and lath.
Expanded metal or wire lath should be cleaned and the
mesh opened, so when patching plaster is forced into
the opening, a good key is formed. Break out the key
between wood lath so that a new key can be formed
when patching material is forced into place.
Thoroughly wet wood lath before applying patching
plaster. Brush out all loose material, remove all grease
or dirt from surrounding surface areas, and wet the
edges of the groove. Press the first coat of patching
plaster firmly into place, filling the groove nearly to