Masonry restoration work is carried out on both modern and historical buildings. The need for masonry repair arises from various reasons ranging from weathering and seismic movements to poor workmanship and negligence. While the need for masonry restoration is often visually evident, it is essential to consult a masonry contractor or a masonry company about the extent of damage, its cause and the right way to deal with it.
The type of masonry restoration to be undertaken may depend on the type, age, condition and location of a building. Historical buildings have to be handled more sensitively than modern buildings. Structures in areas of high risk seismic activities may follow a different masonry repair policy.
The most common types of masonry restoration are repointing and tuckpointing. The two terms are often taken to have the same meaning, but there is a difference. Repointing involves filling the gaps formed in the damaged mortar joints, and tuckpointing is about replacing the deteriorated mortar with new mortar.
In both cases, the strength and look of the old mortar has to be considered when preparing the new mortar. The new mortar has to bond well with the masonry units, and must not produce any stress that will cause them to flake or crumble. The finished masonry work must also have a consistent and aesthetically appealing appearance.
Replacing and resettling masonry units are types of masonry restoration that are undertaken to deal with loosened, fallen, broken or deteriorated units. Displaced or damaged stones, bricks and blocks may be resettled in place using new mortar, or be replaced with other old units. If similar old units are not available, new ones conforming to the originals may be used. As far as possible, especially with historical buildings, it is advisable to reuse old units. Production methods differ in how units were made in earlier days and how they are manufactured in modern times, and this difference can affect structural strength. Another reason is to get a look matching the original.
Another type of masonry restoration is parging. This involves applying a fine, smooth coat of a strong cement mortar to an exposed wall surface. Parging is done to walls that have had adjoining structures removed. It is not used for walls with basic structural problems.
Cleaning is a type of masonry restoration that is used to clear accumulated dirt or moss growth. It is best to clean surfaces with water, mild chemical cleaners and a soft brush. Abrasive cleaners and methods like sandblasting can erode or damage a structure and should be avoided.
A masonry structure, if it has no underlying problems, can be restored by a simple repainting job. It is essential to strip away the old paint and to ensure that the new one complements the building structure. A restored building should be carefully maintained so that restoration work does not become necessary again in the near future.