Pool coping

In Cambridge Dictionary's architectural sense, coping is a row of stones, bricks or other material, often rounded or sloping, that forms the top part of a wall.

A pool wall is still a wall, so the word travels with it. The CDC's Model Aquatic Health Code says a pool's perimeter deck may include the coping, and where a pool has no perimeter gutter system, the code calls for a coping or a cantilevered decking of reinforced concrete or a material equivalent in strength and durability. How the code's deck terms nest, and where the pool deck begins, is set out on the pool deck glossary entry.

The code also sets a number for that cap: the horizontal overhang of coping or cantilevered decking is not more than 2 inches and not less than 1 inch from the vertical plane of the pool wall. That figure is public-pool design text, from voluntary guidance written for public aquatic facilities, and it is not a residential rule. On a home pool, the coping's dimensions are the pool builder's call.

Outside the code, coping is a stone-industry term. The Natural Stone Institute's Dimension Stone Design Manual, in its travertine chapter, lists copings among the stone elements it details, alongside cornices and projecting belt courses.

So travertine coping is a named product term in the trade, not a word coined for a pool quote. Whether stone at the water's edge should be sealed is a separate question, taken up at should outdoor travertine be sealed. What the coping and the deck around it are made of, concrete pavers, travertine or clay brick, decides which industry's cleaning guidance applies, and the paver materials section of the paver cleaning page sets those apart.

Travertine is a calcareous stone, and the Natural Stone Institute says products containing lemon, vinegar or other acids may dull or etch calcareous stones, a travertine coping piece included. That mark has its own entry at etching.