Re-Pointing

What Is Re-Pointing?

Re-pointing is the process of removing deteriorated mortar from the joints between bricks or stones and replacing it with fresh mortar. The mortar joints in a wall are not just cosmetic - they are an integral part of the wall’s weatherproofing, structural integrity and thermal performance. When mortar fails, water gets in, and water is the enemy of masonry.

Every wall built from bricks, blocks or stone relies on its mortar joints to seal the gaps between individual units. Over decades of exposure to rain, frost, wind and temperature changes, this mortar gradually breaks down. The rate of deterioration depends on the mortar type, the quality of the original work, and the level of exposure - which is why re-pointing is particularly important in coastal East Kent, where buildings face some of the harshest weather conditions in the South East.

Lee on re-pointing

Re-pointing is a specialist trade in its own right, and rather than pretending I’m a full-time pointer, I pass dedicated re-pointing jobs on to a specialist within the Perfect Plastering team. That way the customer gets someone who’s done the work day in day out and knows the materials and the techniques for the age of property they’re looking at. I’ll still take on smaller jobs and incidental pointing as part of a larger render or repair project, but for whole-building re-pointing or anything on a listed property, the specialist takes the lead. It’s the right approach: the right person for the right job.

Why Re-Pointing Matters

Water Protection

Open, cracked or missing mortar joints allow rainwater to penetrate the wall. In a cavity wall, this water may reach the inner leaf and cause damp patches inside. In a solid wall, water penetration is more direct and damaging. Across East Kent, the prevailing south-westerly winds drive rain hard against exposed walls, making sound mortar joints critical for keeping buildings dry.

Frost Damage

Water that penetrates mortar joints freezes in winter, expanding and breaking the mortar further. This freeze-thaw cycle is one of the most destructive forces acting on masonry. Each winter makes the problem slightly worse until the mortar is too far gone to protect the bricks. In severe cases, the brick faces themselves start to spall (flake away) as water freezes within the brick.

Structural Integrity

While a few missing mortar joints will not cause a wall to collapse, widespread mortar failure weakens the wall as a structural element. The mortar distributes loads evenly between bricks; without it, loads concentrate on pressure points and movement can occur.

Appearance

Crumbling, patchy mortar makes brickwork look neglected and tired. Fresh, well-executed re-pointing transforms the appearance of a building, often making a bigger visual impact than repainting or cleaning.

Lee on what customers call about

Most re-pointing calls come in either because the customer’s noticed damp inside and traced it back to failing mortar joints outside, or because the brickwork’s just started to look tired and patchy. Storm damage and frost damage prompt more urgent calls, sometimes after a particularly bad winter you’ll see the mortar visibly crumbling around chimney stacks and gable ends. Coastal properties from Margate through to Folkestone need it more often than inland houses, because of the salt and the wind.

Lime Mortar vs Cement Mortar

The choice between lime and cement mortar for re-pointing is not a matter of preference - it is a technical decision based on the age and construction of the building.

Cement Mortar (OPC-Based)

Suitable for modern properties (post-1919) built with cement mortar and hard engineering or wire-cut bricks. Cement mortar is:

• Strong and rigid
• Relatively impermeable
• Quick to set
• Durable in exposed locations

The standard mix for cement pointing is approximately 1 part cement to 4-5 parts sharp sand, with a plasticiser to improve workability. We use quality Portland cement and source sand that matches the colour and texture of the existing mortar.

Lime Mortar (NHL-Based)

Essential for period properties (pre-1919) built with lime mortar and soft handmade bricks or natural stone. Lime mortar is:

• Softer than the bricks it bonds (acting as a sacrificial element)
• Breathable, allowing moisture to escape through the joints
• Flexible, accommodating slight movement without cracking
• Self-healing, with fine cracks closing through continued carbonation

We use natural hydraulic lime (NHL), typically NHL 3.5 from Singleton Birch or St Astier, mixed with a well-graded sharp sand matched to the original specification. For conservation work and listed buildings, we can also use non-hydraulic lime putty for the most authentic and breathable result.

The Danger of Cement on Old Buildings

One of the most common and damaging mistakes in building maintenance is using hard cement mortar to re-point old brickwork that was originally laid in soft lime mortar. The cement is harder than the old bricks, so instead of the mortar being the sacrificial element that weathers and can be renewed, the brick faces crack and spall. We see this regularly across East Kent - Victorian and Georgian brickwork ruined by well-meaning but inappropriate cement pointing.

If your property was built before 1919, or if the original mortar is clearly lime-based (often identifiable by its lighter colour, softer texture and the presence of white lime inclusions), lime mortar must be used for re-pointing.

Lee on bad cement pointing

I’ve seen too many old buildings ruined by cement pointing applied to soft historic brick. The cement is harder than the brick, so when water gets in and freezes, the brick face cracks and spalls because the cement won’t move. You end up with brickwork that looks like it’s been peppered with shotgun pellets, and the only fix is hacking the cement out and going back to lime. The rule is simple: lime where the original is lime, cement only where the original is cement. Get that the wrong way round on a Victorian terrace and you’re causing damage faster than the weather would.

Our Re-Pointing Process

1. Assessment

We examine the brickwork to determine:

• The extent of mortar failure (full re-point or targeted areas)
• The original mortar type (lime or cement) and composition
• The condition of the bricks themselves
• The joint profile (flush, bucket handle, weatherstruck, recessed)
• Any underlying issues (damp, structural movement, previous bad repairs)

2. Raking Out

Old mortar is carefully removed from the joints to a depth of at least 15-20mm (approximately twice the joint width). This is done using hand tools - a plugging chisel and club hammer, or a specialist mortar rake. We avoid using angle grinders to rake out joints, as they are imprecise, damage brick edges, and create an artificially wide joint. On soft historic brickwork, only hand tools are acceptable.

Raking out to sufficient depth is critical. If old mortar is not removed deeply enough, the new mortar has insufficient key and will fail prematurely.

3. Preparation

Raked-out joints are brushed clean to remove dust and loose material. The joints are dampened with water before pointing - this prevents the dry masonry from sucking the moisture out of the fresh mortar too quickly, which would cause it to crack and fail. For lime mortar pointing, thorough dampening is especially important.

4. Pointing

Fresh mortar is pressed firmly into the joints using a pointing trowel, working from the top of the wall downwards. The mortar is pushed well into the back of the joint to ensure full contact with the brickwork on all sides. We work in manageable sections, filling bed joints (horizontal) and perpend joints (vertical) systematically.

5. Finishing (Tooling)

Once the mortar has firmed up enough to hold its shape (typically 30 minutes to 2 hours depending on conditions), the joints are tooled to the required profile:

• Flush - cut flat with the brick face using a trowel or flat jointer
• Bucket handle - shaped with a rounded jointing tool to create a smooth concave curve
• Weatherstruck - angled with a trowel so the joint sheds water outwards
• Recessed - the mortar is pressed back slightly from the brick face, creating a shadow line that emphasises the brickwork pattern

The profile should match the original pointing style of the building. For period properties, flush or slightly recessed joints are usually appropriate. The modern bucket handle profile, while neat, can look out of place on Georgian or Victorian brickwork.

6. Curing

For cement mortar, the pointing should be kept damp for at least 24 hours if conditions are hot or windy. For lime mortar, curing is more critical - lime pointing must be protected from drying too quickly, direct sun and frost for several days. We use damp hessian or sheeting to protect lime mortar during the curing period.

Lee on technique

The technique for good pointing isn’t a secret, it’s just discipline. Rake the joints out to twice their width as a minimum, brush them clean, dampen the wall before you point, and don’t try to tool the mortar until it’s firmed up properly. Working from the top down stops fresh mortar smearing onto finished joints below. The single biggest mistake I see other people make is using an angle grinder to rake out joints on old brickwork, it chews the brick edges to pieces and gives you an artificially wide joint that never looks right. Hand tools take longer but they’re the only correct way on a soft brick property.

Coastal Kent: Special Considerations

East Kent’s coastline presents particular challenges for masonry and mortar. Properties in Dover, Deal, Folkestone, Sandwich, Ramsgate, Broadstairs and Margate face:

• Salt-laden air - sea salt is corrosive and accelerates mortar decay
• Driving rain - prevailing south-westerly winds push rain hard against exposed elevations
• Temperature extremes - coastal locations experience more freeze-thaw cycles than sheltered inland areas
• Wind exposure - constant wind abrades mortar joints over time

For coastal properties, we ensure mortar mixes are appropriate for the exposure level. Cement mortars may be specified slightly stronger (3:1 rather than 4:1) for maximum weather resistance. For lime mortar on period coastal buildings, NHL 3.5 or NHL 5 provides the balance of breathability and durability needed in exposed locations.

We also check and address the condition of copings, sills, lintels and other features that shed water away from the wall face. A failed coping or missing drip detail can funnel water into the brickwork below, undermining even the best re-pointing job.

Chimney Re-Pointing

Chimney stacks are among the most exposed parts of any building and are often the first element to need re-pointing. Projecting above the roofline, they face the full force of wind, rain, frost and temperature changes. We carry out chimney re-pointing as a standalone service (access dependent) or as part of a wider re-pointing project. Chimney work typically requires scaffolding or a cherry picker for safe access.

Lee on chimney re-pointing

Chimneys are some of the most exposed parts of any property and they’re often the first thing to need re-pointing. The challenge is access more than the work itself, you need scaffolding or a cherry picker for safe access, and that adds to the cost. I’ll usually combine chimney pointing with any other roof-level work that’s needed so the customer isn’t paying for scaffolding twice. Coastal chimneys take a battering year-round, and on properties near the seafront I’ll often see chimneys that need re-pointing every fifteen to twenty years rather than the thirty to fifty you’d expect on a sheltered inland property.

Getting a Quote

We provide free assessments and quotations for all re-pointing work across East Kent. We examine your brickwork, identify the correct mortar type and specification, and provide a clear price for the work. We cover Canterbury, Whitstable, Herne Bay, Faversham, Dover, Deal, Sandwich, Ramsgate, Broadstairs, Margate and all surrounding areas.