What is wrong with my wall?
- Feb 15
- 3 min read
Updated: 6 days ago
Pointing terminology can feel like a completely different language, so here’s a simple guide to the most common repointing terms. Use this quick explanation to understand the basics when talking about brickwork or mortar repairs:
Common brickwork and wall problems
Spalling
Spalling is the flaking, cracking, or breaking away of a brick or stone surface, which allows water to penetrate the masonry and can lead to damp problems inside your home. It is usually caused by moisture trapped in the brick or stone because mortar previously used is too hard, or spalling happens with age over time.
Solution: affected bricks should be turned or replaced to restore the wall’s strength and prevent further damage.
Brickwork Variegation:
Brickwork variegation refers to noticeable variation in colour, tone, or texture between bricks within the same wall.
This uneven appearance can occur naturally or result from poor repairs, mismatched bricks, or areas where windows or doors have been bricked up.
Solution: if the inconsistency affects the look of your wall, you can replace the most visually different bricks or adjust the mortar joints to blend previously altered areas more effectively.
Damp ingress
Damp ingress, also referred to as penetrating damp, occurs when water enters a property through an external wall. Penetrating damp specifically refers to moisture getting in through damaged mortar joints, cracks, or gaps in the brickwork. This can lead to internal damp patches, mould, and long‑term structural problems.
Solution: repoint the wall with the correct mortar for the bricks or stone and repair or replace any damaged bricks to stop water penetration and protect the building.
Rising damp
Rising damp is a term often used to describe a range of moisture problems, including condensation, penetrating damp, plumbing leaks, splashback from hard surfaces, or damp‑course failure/bridging.
True rising damp is less common, but when a damp‑proof course has failed, it must be assessed and repaired by a specialist damp‑proofing company. (I recommend contacting Damp Proofing Nottingham | Midland Preservation Ltd — I have no affiliation with the company.)
Solution: if the dampness is caused by water splashing against the wall, condensation, or damp ingress through damaged mortar, then repointing the wall and repairing or replacing damaged bricks is often an important part of the solution.
Efflorescence, also known as surface salts
Efflorescence (or surface salts) appears as white, powdery patches on the outside of a wall. It is common and completely normal on newly built houses for the first six months as moisture evaporates from fresh materials. However, persistent efflorescence on older walls usually indicates that water is penetrating the brickwork or mortar.
Solution: inspect the wall for damaged bricks or failing mortar joints and repair or replace them to stop moisture entering the wall.
Compressive strength
Compressive strength refers to the amount of pressure a material can withstand before it begins to fail.
In brickwork, it’s important that the bricks have a slightly higher compressive strength than the mortar. This ensures that moisture is absorbed and released through the mortar — not through the bricks — helping to prevent damp problems, spalling, and long‑term damage to the masonry.
When the mortar is harder than the bricks or stone, the masonry can fail before the joints do. This often leads to spalling, where the faces of bricks or stone break away, exposing the wall to further moisture and damage. This problem is common when cement‑based mortar is used on older homes built with softer, less dense bricks or stone.
Over time, this mismatch spoils the appearance of the wall and shortens the lifespan of the masonry.
Solution: use lime mortar, which is softer and breathable, and repair or replace any damaged bricks or stone to restore the wall and prevent future deterioration.
