Masonry resistance against water penetration depends on materials used, types of wall, and quality of workmanship. Methods to improve water penetration resistance of masonry is discussed.
There are number of methods by which the masonry water penetration resistance can be further increased.
These methods, which are explained in this article, can be categorized into two major groups which are methods related to masonry design and methods related to masonry construction.
Fig.1: Masonry Structure
- Methods to Improve Masonry Resistance Against Water Penetration
- Methods Related to Design and Specifications of Masonry
- Design of Drainage Wall to Improve Water Penetration Resistance of Masonry
- Cavity walls Design to Improve Masonry Water Penetration Resistance
- Design and Detail Consideration to Make Rooms for Differential Movements
- Construction Methods to Improve Masonry Water Penetration Resistance
Methods to Improve Masonry Resistance Against Water Penetration
- Methods related to design and specifications of masonry
- Methods of masonry construction
Methods Related to Design and Specifications of MasonryIt is advised to select and design type of a wall that is suitable for the degree of forced rain severity anticipated in the location of the project. Completely grouted barrier wall or drainage wall with minimum thickness of 20 mm is recommended for seriously driven rain condition.
Design of Drainage Wall to Improve Water Penetration Resistance of MasonryWhen drainage wall is selected, the wall should be designed in such a way that prevents the water penetration through the outer Wythe of the wall. For the outer Wythe masonry wall maintain its water resistance ability, cracks under service load should be prevented. When masonry cement is employed, the lower tensile bond strength of the cement should be considered in specifying whether the veneer will crack or not whereas if steel studs are utilized it is recommended to consider the steel flexibility in determining whether the veneer cracks or not. The sealant of the outer Wythe joint must be specified carefully to prevent rainwater penetration through joints.
Fig.2: Drainage Masonry Wall
Cavity walls Design to Improve Masonry Water Penetration ResistanceIf the cavity wall is determined to be employed, the design needs to be carried out to maintain the wall open and drained successfully. Appropriate flashing and weep holes must be determined to drain water out of the wall cavity in the case it enters the wall cavity. Masonry wall cavity should be kept clean by employing a board to remove mortar debris and 50 mm is advised to be used for the cavity width. Interstitial condensation must be avoided within the inner Wythe and this may be obtained by vapor barrier on the exterior face of interior Wythe. Either stainless steel or hot dip galvanized ties is recommended to apply.
Fig.3: Cavity Masonry Wall