Top 5 common structural issues in UK buildings (and how to fix them)

In this blog we look at the five common structural issues in UK buildings and what typically works to fix them. These aren’t just theoretical problems; they’re the ones that pop up time and time again in surveys, refurb projects, and insurance claims.

1. Subsidence

What it is: 

Ground movement under foundations, often due to shrinkable clay soils, tree roots, or leaking drains. Shows up as stepped cracks in walls, doors that stick, or sloping floors.

How to fix it:

• Tree management: Prune or remove trees that are too close to the building.

• Drainage repairs: Fix leaking pipes and ensure surface water is directed away.

• Underpinning: Strengthen foundations with concrete or resin injection if movement is progressive.

Heads-up: 

It’s often monitored before action. Insurance may require data over a year or more before approving underpinning.

2. Cavity Wall Tie Failure

What it is: 

Metal wall ties corrode, especially in 1930s–1980s builds. This weakens the bond between inner and outer walls, risking bulging or collapse.

How to fix it:

• Wall tie survey: Identify tie type and extent of corrosion.

• Remedial ties: Install stainless steel or other corrosion-resistant ties.

• Decommission old ties: Cut or isolate failed ones to prevent expansion damage.

Tip: 

Wall cracking in regular horizontal lines can be a giveaway. Early detection = cheaper fix.

3. Roof Spread

What it is: 

Roof pushes outwards on walls, usually because of failed or undersized roof ties (especially in older buildings). Can lead to bulging walls or cracked masonry.

How to fix it:

• Strengthen ties: Add or reinforce ceiling joists or steel straps to tie rafters and walls together.

• Rafter repair: Replace decayed timber where needed.

• Wall plate anchoring: Secure roof structure to wall plates properly.

Clue: 

Often turns up after a loft conversion where original structural intent was overlooked.

4. Damp & Timber Decay

What it is: 

Water ingress leads to rot in structural timbers, particularly in suspended floors and roof structures. Often linked with poor ventilation, bridging damp-proof course (DPCs), or guttering faults.

How to fix it:

• Source control: Fix leaks, unblock gutters, and lower ground levels if bridging is occurring.

• Ventilation: Improve underfloor and roof void airflow.

• Timber replacement: Cut out decayed areas and treat adjacent timber.

Watch for: 

Musty smell, bouncy floors, and discoloration around skirtings or ceiling lines.

5. Lintel Failure

What it is: 

Cracked brickwork above windows/doors due to corroded or undersized lintels. Common in properties from the 1950s–70s with steel angle lintels that rust and expand.

How to fix it:

• Expose and inspect: Check lintel condition behind the brick face.

• Replace lintel: Use concrete, steel, or proprietary systems to match structural needs.

• Re-point & make good: Reinstate brickwork carefully to avoid further stress.

Flag: 

Diagonal cracks at window corners and dropped brick courses can signal trouble.

Final Thought

None of these are one-size-fits-all. The right solution depends on the building's age, materials, use, and local conditions. Always worth backing up with a structural survey, especially before committing to invasive works.

Noticed the signs? Start with certainty.

At OMNIA, we don’t just diagnose, we help you understand the “why” behind building issues, so you can plan smarter. Our Building Pathology services combine deep technical insight with practical, forward-thinking solutions that protect value and future-proof your assets.

Explore how we support clients across the UK: Building Pathology Services

Or get in touch directly, we're here to help you see the full picture before you commit to the next move.