Brick Repair near you

Spalling is the classic British brick failure. Water soaks into a porous brick, freezes, expands and pushes the face off, and once the face has gone the exposed core absorbs even more water and fails faster. The freeze is rarely deep in this climate, but it is frequent, and repeated shallow frosts do more to an already wet wall than one hard winter does to a dry one.

Where the water comes from matters more than the frost. A brick wall that is wetted only by ordinary rain and dries between downpours generally survives; one that is soaked every time it rains by a blocked gutter, a leaking downpipe, splash-back from a raised path, or ground raised above the damp-proof course, does not. The Planning Portal's description of a damp-proof course is a layer installed to prevent rising or penetrating damp by preventing moisture entering the walls, and bridging it with soil, paving or render is one of the most common causes of decayed brickwork at low level.

The third cause is self-inflicted. Repointing an old, soft wall in a hard cement mortar leaves the joints stronger than the bricks, so the wall's movement and its moisture are forced through the brick faces instead of the joints. The pointing survives and the bricks do not. The same logic applies to impermeable paints and sealants sold as waterproofing: whatever gets behind them cannot get back out.

Repointing begins with removal, and removal is where elevations are destroyed. Joints are raked out to a depth of roughly twice their height so the new mortar has something to hold, and on soft or narrow joints that is done by hand rather than with a disc. An angle grinder run along a Victorian wall widens the joints, cuts the arrises off the bricks and leaves a permanent tram-line effect, quite apart from the dust it throws. Where power tools are used at all, HSE's position on construction dust is the relevant one: silica is a major constituent of materials such as bricks, tiles, concrete and mortar, dust is generated by cutting, drilling, grinding and polishing, and regularly breathing it can cause lung cancer, asthma, chronic obstructive pulmonary disease and silicosis.

The wall is then dampened as required by the mortar being used, the joints are filled in layers rather than in one smear, and the finish is matched to the original profile, whether that is flush, bucket-handle, weather-struck or a struck and tuck detail. A lime mortar needs protecting while it cures, from sun and wind as much as from frost and driving rain, which is why a conscientious firm hangs hessian and works to the weather rather than to the diary.

Replacing individual bricks follows the same discipline. The failed unit is cut out without disturbing its neighbours, the recess is cleaned back, and a matching brick is bedded and pointed to match. Where a matching brick cannot be had, a sound brick can sometimes be turned or taken from a hidden elevation and the gap made good there. Cutting out and reversing bricks, rather than rendering over a tired wall, is usually the repair that keeps the house looking like itself.

Ordinary repair sits outside the approval system. The Planning Portal's general position on external walls is that you do not need to apply for planning permission for repairs, maintenance or minor improvements. Two things change that. The first is scale: the building regulations guidance on external walls is that where 25 per cent or more of an external wall is re-rendered, re-clad, re-plastered or re-lined internally, or where 25 per cent or more of the external leaf of a wall is rebuilt, the regulations would normally apply and the thermal insulation would normally have to be improved. Rebuilding a quarter of an outer leaf is therefore a different conversation from replacing forty bricks.

The second is heritage. National planning practice guidance states that works to alter a listed building in a way that affects its character as a building of special architectural or historic interest require listed building consent, that carrying out such works without consent is a criminal offence, and that even minor works have the potential to cause substantial harm depending on their impact on the asset and its setting. Repointing is precisely such a work: the mortar, its colour and the joint profile change the appearance of an entire elevation. Permitted development rights are also more restricted in conservation areas, so ask the local planning authority before the scaffold goes up.

The devolved picture differs. Scotland's list of work not requiring a building warrant includes the replacement of a fitting or equipment, in whole or in part, by another of the same general type, and similarly the replacement of flooring, lining, covering or rendering, provided the work is to a standard no worse than at present, with anything beyond that going to the council's building standards department. Northern Ireland uses technical booklets, with Booklet C covering site preparation and resistance to contaminants and moisture and Booklet D covering structure.

Spot repair is right where the failure is local and the cause has been dealt with: a handful of spalled bricks under a leaking hopper, a metre of open joint on an exposed corner, a coping put back on a garden wall. Repointing a whole elevation becomes the better answer when the joints have failed generally across a face, because patching in a different mortar and a different profile every few years produces a chequerboard that looks worse than the decay did.

Rebuilding is the answer when the brickwork has lost its integrity rather than its surface: bulging or bowing, bricks that move, a failed lintel with the courses above it dropped, or a garden wall leaning beyond recovery. That is structural work and belongs with Approved Document A, the England guidance covering the loadings on a building and the construction of the structural elements including the foundations, walls, floors, roofs and chimneys. Rendering over failing brickwork to avoid the decision is the one option worth ruling out at the start; it hides the symptom, adds weight and, if the render is impermeable, accelerates what is happening behind it.