Mortar joints protect the edges of bricks and help the wall manage moisture. Over time, weathering, frost, unsuitable past repairs or structural movement can cause joints to crack, erode or fall away. Repointing restores the joint, but it should only follow an assessment of why deterioration has occurred.
Signs repointing may be needed
Recognising failing mortar
Look for deep or powdery joints, loose mortar, open gaps, vegetation growth and damp patches associated with exposed masonry. Chimneys, parapets and west-facing elevations often experience greater weathering.
Check for movement first
Using compatible materials
Repointing is not a structural repair. Stepped cracks, displaced bricks or recurring openings may indicate movement that needs separate investigation. Filling an active crack can hide changes without resolving the cause.
Use compatible mortar
Protecting the work while it cures
Mortar should generally be softer and more vapour-permeable than the surrounding brick. A very hard cement-rich mix can force moisture and weathering into softer bricks, leading to damaged faces. Older properties may require a lime-based approach.
Preparation affects durability
Failed mortar should be removed to a suitable depth without damaging the brick arrises. Joints are cleaned, controlled for moisture and refilled in layers. Smearing mortar over the face of the wall is not a substitute for proper joint preparation.
Match joint profile and appearance
Flush, recessed, weather-struck and other profiles create different appearances and weathering characteristics. The existing building and local character should guide the choice. Test panels can help agree colour and finish before large areas are completed.
Related work to inspect
- Cracked or spalled bricks.
- Failed window and door sealants.
- Leaking gutters and downpipes.
- Chimney pots, flaunching and leadwork.
- High ground levels against the wall.
Protect the work while it cures
Fresh mortar can be damaged by heavy rain, strong sun or frost. The contractor may need to use sheeting, controlled dampening or temporary protection so the joints cure evenly. Rushing the drying process can lead to cracking, weak joints or colour variation.
Cleaning methods also matter. Aggressive pressure washing or acid can damage bricks and alter mortar colour. Any cleaning should be tested on a small, discreet area first.
- Agree a sample panel before full production.
- Check weather protection arrangements.
- Avoid sealing walls without understanding moisture movement.
- Retain spare matching bricks for future repairs where possible.
How Essex Construction Can Help
Essex Construction provides professional construction, refurbishment and property improvement services across Essex. Contact Essex Construction to arrange a site assessment and discuss the most suitable next steps for your property.
