Copings are the topping for a wall. Their purpose is to prevent rainwater running down the face of the brickwork, which can lead to problems with damp and colonisation by algae and other vegetation.

Retainer walls are used to hold back a bank of earth or similar. They range from small walls in a garden, holding back raised beds, to massive structures, 10m or more high, retaining a motorway embankment. Retainer walls are not as straightforward as simple walls, and any such walls greater than 1m high should be designed by a civil or structural engineer who is familiar with site and ground conditions. For low embankments, 600mm or less, a flag on edge retainer may well be adequate, and will certainly be cheaper than a brick-built wall. Other options include gabions, timber crib structures or proprietary retaining wall systems. Contact details suppliers of these products can be found on the links page. This diagram illustrates a basic retainer wall for heights up to about one metre. The important points to note are that the foundation is laid on a solid base of clay or stable ground, or with 300mm of cover; that the rear of the wall, in contact with the earth, should be protected with a damp-proof membrane such as PIFA 1200, and that there should be some method of draining the bank, either via weepholes or by means of a perforated drain. It is essential that the correct bricks are used. 'House bricks' may or may not be suitable, depending on classification. Engineering bricks are fine, as are any other bricks with a FL classification (frost resistant/low salt content). Stone or suitable concrete blocks could also be used. If in doubt, seek professional guidance.