Coping and capping

Cappings and copings are used to cap the tops of masonry parapets and freestanding walls to prevent rainwater from penetrating into the construction below. They can be made from profiled metal such as lead, aluminium, zinc, copper and plastic-coated steel, or by using special bricks or masonry.

Irrespective of the materials from which they are made, a coping will typically project by around 50mm on either side of the wall, whereas a capping will sit flush to the wall with no projections.

Copings have projections to throw water as far as possible from the wall surface below. This is facilitated by the inclusion of drips – typically 10mm-wide semi-circular grooves cut into the underside of the projections – designed to prevent wind-driven rain from being blown back against the wall.

Because of their position, cappings and copings are exposed to temperature extremes and frequent wetting/drying cycles. As they are more exposed than ordinary walling, they should be made of materials that have greater resistance to frost and sulphate action. To assist with water run-off, the tops of copings and cappings typically feature either a single or double slope.

In most cases, the coping/capping arrangement will not be completely water tight. Therefore, to avoid water penetration into the wall below, a damp-proof course is usually installed beneath the coping/capping.

NB Short Guide: Climate Change Adaptation for Traditional Buildings, published on 10 July 2017 by Historic Scotland, defines a cope as a: ‘Masonry or concrete slab projecting over a masonry element, designed to shed water.’

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