We’ve seen a number of moisture issues appearing on relatively new commercial shopping centers recently and the culprit has been failed caulking.  It serves as an important reminder to building owners and property managers that while caulking is a small part of a structure, it plays an important role in keeping a building watertight. Both new and old buildings can be vulnerable to failed caulking.

The wrong caulking or improperly applied caulking is a major cause of moisture problems. Moisture stains are a sign that the caulking has failed.  Look below windows or near the roof line.  Windows and roofs are especially prone to water penetration.  By conducting regular inspections and paying attention to minor repairs, building owners can avoid major repairs down the road.

Reasons for Caulking Failure

Sometimes shoddy construction can lead to a leaky facade.  In the rush to finish a job or faced with inadequate supply, a contractor might use whatever caulking is on hand, rather than what was specified. Use of the wrong sealant with masonry and concrete can cause  discoloration, stress on concrete or even spalling.

In other cases, joints that are too narrow or wide can cause the caulking to fail. If the joints are too narrow, the expansion of the substrate can cause the joints to close too much and extrude the sealant. Later when the building contracts, the caulking is no longer in the joint. If a joint is too wide (more than one or two inches, depending on the sealant), the sealant may sag out of it.

Misapplication may also be due to weather.  Brick or masonry must be completely dry to get proper adhesion with caulking. Applying when moisture is present causes the sealant to lose viscosity. It is too thick to properly tool.  Similarly, applying caulking when it’s too hot can cause the sealant to sag or even flow out of the joint.

At Shamrock Tuckpointing we take caulking seriously. With careful selection of the proper sealants for the job and application, we make your commercial building watertight.