Cement mortar repointing for brick and stone properties
Mortar joints are not decorative. They bind masonry units together, protect the wall from water penetration and allow the structure to flex slightly without cracking. When mortar fails, rain gets in. Over time, water in the joint cycles through freeze and thaw in winter, expanding and accelerating deterioration.
Cement mortar repointing removes failed mortar and replaces it properly - restoring the wall's weather resistance and protecting the brickwork beneath.
When cement repointing is appropriate
Cement mortar is typically the right material when:
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The building was originally constructed and pointed with a cement-based mortar
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Mortar joints are visibly cracked, recessed or falling out
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Rain is penetrating the wall through open or failed joints
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The building is of modern or post-war construction (broadly: 1920s onwards)
Using cement on a building originally constructed with lime mortar is a separate issue and can cause significant damage. If you are unsure which applies to your property, see lime mortar repointing or consider a Building Leak & Damp Inspection first.
What cement repointing actually involves
Raking out failed mortar
The first step is removing defective mortar to a minimum depth of 15 to 25mm. This is not optional - shallow raking is one of the most common reasons repointing fails early. A thin sliver of new mortar applied over shallow removal does not have enough mass to bond properly or resist weather.
Raking is done carefully to avoid damaging the arrises - the sharp edges of the brick or stone. A damaged arris affects both appearance and weather resistance, because water runs along and into chipped edges rather than shedding cleanly from a sharp line.
Matching mortar to the existing
Before we mix anything, we assess the existing mortar for colour, aggregate texture and joint profile. Repointing that does not match the surrounding mortar is immediately visible and is a sign the specification was not considered carefully.
Colour matching involves both the cement-to-sand ratio and the sand type. Yorkshire sandstones and older brick beds have a variety of surrounding mortar colours - buff, silver, grey, brown - and the right sand sourcing makes a significant difference.
Joint profiles
Different properties have different joint profiles.
Common ones we work to include:
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Flush - mortar finished level with the brick face; clean and modern appearance
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Weathered - top edge slightly recessed to encourage water to shed away from the face
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Bucket handle (concave) - a rounded, slightly recessed profile common on older domestic brickwork; effective at shedding water
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Recessed (raked-out) - mortar set back from the face to create a shadow line between courses; applied with a chariot or shaped tool drawn along the fresh joint
We finish joints to match the existing profile unless there is a functional reason to change it.
How long does cement repointing take?
The scale of the work determines the timescale:
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Localised repointing - a chimney stack, a few courses around a lintel or a short run of joint failure - may be completed in a single visit, typically a few hours
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Single elevation - a front or rear elevation on a standard semi-detached can usually be completed within one to two days
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Full building - larger properties, multiple elevations, or buildings with more extensive joint deterioration will take several days
We will advise on a realistic timescale when we assess the work.
Weather conditions and curing
Cement mortar sometimes requires protection during curing. We do not point in frost conditions - mortar that freezes before it has cured will fail. Similarly, direct hot sun and high winds can cause the mortar to cure too quickly and crack.
New pointing benefits from being kept slightly damp for the first 24–48 hours in hot, dry weather to slow the cure and reduce shrinkage cracking. Where conditions require it, we use appropriate admixtures - including SBR bonding agents to improve adhesion on difficult substrates, plasticiser to improve workability and reduce water content, and frostproofer in cooler temperatures where there is a risk of an overnight freeze during the curing window.
Why cheap repointing fails
We regularly see previous repointing that has failed far too quickly. The most common causes:
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Shallow raking - insufficient removal depth means there is no key for the new mortar and it pulls away in sheets
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Wrong mortar mix - mortar that is too strong can cause the brick faces to spall; too weak and it erodes rapidly
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Poor preparation - joints that are not clean and damp before pointing see poor adhesion and early failure
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Incorrect joint finishing - flush joints that stand proud of the brick face trap water rather than shedding it
Getting these details right is what separates pointing that lasts from pointing that needs redoing inside a few years.
Where we carry out cement repointing
We carry out cement repointing regularly across Bradford, Leeds, Harrogate, Halifax, Skipton, Wetherby and surrounding areas. Yorkshire's climate - high rainfall, cold winters, exposed hillside positions - means mortar joints work hard. Done correctly, cement repointing on a post-war brick property should last 20 to 30 years.
Where mortar failure is accompanied by damaged or spalled brick faces, repointing is typically combined with masonry repair.
Frequently asked questions
Q1. How long does cement repointing last? Correctly applied cement pointing on a modern brick building should last 20 to 50 years. Exposure, the original brick or stone quality and the mortar specification all affect longevity. Q2. Does all the mortar need removing? No. Only defective joints - those that are cracked, recessed, loose or failed - are raked out and replaced. Sound mortar that is still bonded and protecting the wall is left in place. Q3. Will repointing stop damp inside the house? If rain is penetrating through failed mortar joints, correctly executed repointing should significantly reduce or eliminate that ingress. If damp has other causes, it may not resolve fully - which is why diagnosis matters. Q4. Can you match the colour of the existing pointing? In most cases, yes. We assess existing mortar before specifying a mix and select aggregate to match the colour and texture as closely as possible. Q5. What does cement repointing typically cost per square metre? As a guide, cement repointing in Yorkshire typically costs in the region of £40–90 per square metre, depending on joint condition, depth of raking required, accessibility and the area involved. Ground-level work on a straightforward elevation is at the lower end; scaffolded or multi-storey work with heavily eroded joints will cost more. We provide written itemised quotes after inspecting the property - cost is confirmed before work starts. Q6. Do you repoint the full elevation or just the joints that have failed? It depends on the condition of the existing mortar. If the majority of joints on an elevation are failing, a full elevation repoint is more cost-effective and visually consistent than spot repairs. If only a proportion are defective, targeted repair is appropriate. We will not carry out more work than is necessary.
Not sure if this is the right repair?
If mortar failure is widespread or you are unsure whether cement or lime mortar is appropriate for your building, a Building Leak & Damp Inspection will establish the correct approach before any work begins.