One of the greatest challenges with masonry buildings is water entering the building envelope, causing freeze-thaw damage and other problems such as mold.
Water sealing would seem like the obvious solution and is one of the most misunderstood and damaging treatments for brick buildings.
Older sealers and paints created a film that did not allow water into the building and created a surface barrier. In time, these coatings peel off the buildings creating an eyesore. Certain coatings cause the outer layer of masonry to be pulled off the building with it causing damage. Even greater damage occurs when the water is trapped in the wall, causing freeze/thaw damage.
Current masonry “sealers” are not really sealers at all but rather are water repellents that penetrate into the surface and usually do not alter the appearance of the building. Water vapor can both enter and exit the structure as it normally would due to the molecular structure of the repellant. These repellents do prevent water in liquid form from entering the structure and allow water vapor out. However, water repellents can also trap water in liquid form inside a building envelope.
Most historic buildings do not require water repellents and incorrect use can cause more damage than they prevent. They should be considered only when it is deemed necessary to preserve very soft absorbent brick or in certain areas of a structure at higher risk due to higher exposure to weathering.
Rising Damp (water entering building from the ground by capillary action) can cause waterproofing problems as well as can coping, parapet wall, and cap failure. Alliance can partner with you in solving these often complex issues.
There are a myriad of potential issues that can cause waterproofing problems in masonry buildings so there is no one-size-fits-all approach to water management for masonry.
Alliance Restoration and Preservation Services can assist you in correcting the waterproofing challenges your building brings. We offer solutions in flashing and sealing as well as parapet and coping caps. Foundation treatments and water diversion solutions are all part of a comprehensive plan for your buildings’ longevity.
Joshua Dunn is the owner of Alliance Restoration LLC, a Kansas City based masonry restoration contractor and consulting service that focuses on traditional methods in masonry construction and up-to-date preservation techniques to maintain our built heritage.