Repointing is both expensive and time consuming due to the extent
of handwork and special materials required. It is preferable to
repoint only those areas that require work rather than an entire
wall, as is often specified. But, if 25 to 50 per cent or more
of a wall needs to be repointed, repointing the entire wall may
be more cost effective than spot repointing.
Total repointing may also be more sensible when access is difficult,
requiring the erection of expensive scaffolding (unless the majority
of the mortar is sound and unlikely to require replacement in
the foreseeable future). Each project requires judgement based
on a variety of factors. Recognizing this at the outset will help
to prevent many jobs from becoming prohibitively expensive.
In scheduling, seasonal aspects need to be considered first.
Generally speaking, wall temperatures between 40 and 95 degrees
F (8 and 38 degrees C) will prevent freezing or excessive evaporation
of the water in the mortar. Ideally, repointing should be done
in shade, away from strong sunlight in order to slow the drying
process, especially during hot weather. If necessary, shade can
be provided for large-scale projects with appropriate modifications
The relationship of repointing to other work proposed on the
building must also be recognized. For example, if paint removal
or cleaning is anticipated, and if the mortar joints are basically
sound and need only selective repointing, it is generally better
to postpone repointing until after completion of these activities.
However, if the mortar has eroded badly, allowing moisture to
penetrate deeply into the wall, repointing should be accomplished
before cleaning. Related work, such as structural or roof repairs,
should be scheduled so that they do not interfere with repointing
and so that all work can take maximum advantage of erected scaffolding.
Building managers also must recognize the difficulties that a
repointing project can create. The process is time consuming,
and scaffolding may need to remain in place for an extended period
of time. The joint preparation process can be quite noisy and
can generate large quantities of dust which must be controlled,
especially at air intakes to protect human health, and also where
it might damage operating machinery. Entrances may be blocked
from time to time making access difficult for both building tenants
and visitors. Clearly, building managers will need to coordinate
the repointing work with other events at the site.