(Article reprinted with the permission of the Brick Institute of America)
ENGINEERING AND RESEARCH DIGEST
Brick Pool Copings
When used as a coping, full round bullnose brick pavers are an attractive enhancement to a pool. However, these pavers can be exposed to the most harsh of weathering conditions, thus requiring thoughtful installation and maintenance to ensure user safety and unit durability.
Careful attention to detailing and installation can prevent the most commonly encountered problems: spalling parallel to the length of the coping above the concrete support, and separation from the concrete support. This E & R Digest presents a suggested installation procedure for full round bullnose brick pavers to be used as pool copings. This procedure is also applicable to projecting stair treads and to other brick in pool copings.
Until present, there have been no recognized procedures for installing pool copings. As individual problems developed as a result of misapplication, the manufacturers of these units have been motivated to develop their own guidelines for proper installation in an attempt to ensure customer satisfaction.
The appropriate choice of material for the pool coping is a full bullnose brick paver complying with ASTM C 902 Specification for Pedestrian and Light Traffic Paving Brick. Of the three weathering classes, Class SX is applicable for most pool coping installations in the contiguous United States, as it is intended for use where the brick may be frozen while saturated with water. Additional information regarding brick paver durability and selection can be found in BIA’s Technical Notes on Brick Construction 14A Revised, Brick Floors and Pavements, part II of III.
Latex-modified Portland cement mortars are recommended for this application. They provide greater durability than conventional mortars while increasing bond strength and reducing water absorption. It should comply with ANSI A118.4 Specification for Latex-Portland Cement Mortar. Mortar Type M is preferred for brick on grade; Type S may also be used for exterior installations not in contact with the earth. These are suitable for pool coping applications.
In the same manner as any other brick masonry construction, the area of application should be clean of debris. Any concrete base should be clean and wetted, but surface dry upon placement of the mortar setting bed. If high initial rate of absorption units are used (in excess of 30g/30 in.2/min [1.5kg/m.2/min]), they should be thoroughly wetted and surface dry when installed.
Using a latex modified Portland cement bedding mortar, lay the desired thickness setting bed no more than two feet (0.6 m) ahead of the coping units. These units should be buttered with mortar on the bottom and edges, and shoved into the mortar bed. Completely fill joints between units. Tool with a concave jointer when the mortar is thumbprint hard.
Expansion joints are necessary in pool copings to prevent differential movement problems. Expansion joints should be installed approximately every ten feet (3 m) on center along the perimeter of the pool coping, as well as any location where the pavers abut a restraining surface such as a curb or wall, as shown in Figure 1. The depth of the expansion should be joint entirely open or filled with a highly compressive material, such as a neoprene or closed-cell foam pad. The top of the joint should be sealed with a backer rod and elastomeric sealant. This is illustrated in Figure 2.
Brick pool copings should be maintained in a manner similar to that of as other pavers. Rubber tipped shovels are recommended for snow removal, and deicers containing rock salt should be avoided to prevent efflorescence. Procedures given in Technical Notes 7F should be followed for any repointing of mortar joints. This should be considered if the mortar softens, deteriorates, or develops visible cracks, in order to minimize moisture penetration.
Swimming pools are often covered throughout the winter. A pool cover can trap moisture-laden air around the brick pool coping and potentially encourage freeze-thaw deterioration throughout the winter in areas subject to freezing conditions. Therefore, use a pool cover that does not enclose the brick pool coping in such locations.