The Enterprise Property Group undertook masonry repairs on a shopping plaza in Mississauga in 1995. Property Manager Al King was looking for a solution which would put an end to a persistent problem of moisture penetration into his tenant’s units through three 90 foot long, masonry gables which intersect the building in the middle of the units.
Each of these walls was constructed with 10″ block, a brick veneer on front and rear of the walls with a precast cap on the top of the gable. Inspection found the wall to be saturated with water resulting from a leaky cap and wind driven rain through the masonry. Water was simply traveling through the wall until it hit the steel it was built upon at which point it dripped directly into the unit below.
The chief task of technician Geoff Grist was to install a membrane near the base of the wall above the roof to eliminate the possibility of the passage of moisture through the masonry. A six course high band of brick was removed in four foot sections to expose two courses of concrete block which were then also removed. A course of semi-solid block was laid and then a self adhering bituminious membrane manufactured by Grace was installed across the top of the brick and block and up the back of the brick veneer on the other side.
All the seams were caulked with mastic caulking. Ends of vertical pieces of structural steel intersecting the masonry were wrapped in the membrane material and thoroughly sealed to prevent moisture from traveling into the building across the steel. The second course of block was then relaid into the cavity on top of the membrane. Then the brick was also relaid over the membrane layer with brick vents installed to allow the escape of any moisture. Finally the roof membrane had to be refastened to the wall and reflashed.
The other phase of the project was to eliminate water penetration through the replacement of damaged bricks, repointing joints, caulking the concrete cap and applying an appropriate masonry sealer to inhibit the entrance of moisture.
The above approach attacked the problem at each point of weakness resulting in a repair of excellent quality.