Top 10 Building Defects Found in Commercial Property Surveys

My Commercial Building Surveyors have inspected thousands of commercial properties across the UK over the past two decades. Through this extensive experience, our RICS chartered surveyors have identified recurring building defects that appear across offices, warehouses, retail units, and industrial facilities. Understanding these common issues helps property owners, investors, and tenants recognize potential problems early—before they escalate into costly structural repairs or safety hazards.

This expert guide reveals the top ten building defects our experienced team of surveyors discovers most frequently during commercial building surveys, explaining what causes each problem, how to identify warning signs, and why addressing these issues promptly protects your property investment.

1Roof Water Ingress and Deterioration

Roof defects are by far the most common issue discovered during commercial building surveys. My Commercial Building Surveyors find roof problems in approximately 60-70% of properties we inspect. Water ingress through damaged roofing can cause catastrophic damage to the building structure, internal finishes, and business operations.

Common Roof Defects Include:

• Failed flat roof membranes: Cracking, blistering, or splitting of bituminous felt, single-ply membranes, or asphalt roofing
• Missing or damaged roof tiles: On pitched roofs, storm damage or deterioration creates entry points for water
• Defective flashings: Failed seals around roof penetrations, parapets, and abutments
• Blocked or damaged gutters: Inadequate rainwater disposal causes overflow and water penetration
• Ponding water: Poor falls on flat roofs leading to standing water that accelerates membrane failure

Why This Matters:

Roof repairs represent one of the highest costs in commercial building maintenance. A full roof replacement for a typical commercial unit can cost £40,000-£150,000+. Early identification through professional surveys allows targeted repairs at a fraction of replacement cost.

2Cracking and Structural Movement

Our building surveyors regularly identify cracking in commercial properties, ranging from minor cosmetic issues to serious structural defects. Not all cracks indicate structural failure, but distinguishing between harmless settlement and progressive movement requires expert assessment.

Types of Cracking We Identify:

• Vertical cracks: Often indicate settlement or thermal movement
• Stepped cracks in brickwork: May suggest foundation issues or structural movement
• Horizontal cracks: Can indicate wall tie failure or inadequate lateral restraint
• Diagonal cracks from openings: Often caused by lintel deflection or inadequate support

My Commercial Building Surveyors use crack monitoring equipment and structural analysis to determine whether movement is historical (stabilized) or progressive (ongoing). Progressive movement requires immediate investigation and potential underpinning or structural reinforcement.

3Rising and Penetrating Damp

Moisture problems affect approximately 40-50% of commercial buildings we survey. Damp causes structural damage, promotes timber decay, creates unhealthy working environments, and can force business closures if left untreated.

Common Dampness Issues:

• Rising damp: Failed or absent damp-proof courses allowing ground moisture to rise through walls
• Penetrating damp: Water ingress through defective pointing, cracked render, or failed seals
• Condensation: Inadequate ventilation causing surface moisture and mold growth
• Plumbing leaks: Hidden pipe failures within walls or floors

Detection Methods:

Our experienced surveyors use moisture meters, thermal imaging cameras, and visual inspection to identify damp problems. We distinguish between different moisture sources because each requires specific remediation—treating rising damp won't solve a roof leak problem.

4Defective or Deteriorated Windows and Doors

Commercial property windows and doors suffer significant wear from constant use, weather exposure, and aging mechanisms. My Commercial Building Surveyors find defective windows and doors in 50%+ of properties we inspect.

Typical Window and Door Defects:

• Failed double glazing seals: Condensation between panes indicating seal failure and lost thermal performance
• Deteriorated timber frames: Rot in wooden windows requiring replacement
• Corroded metal frames: Rust in steel windows reducing structural integrity
• Defective opening mechanisms: Failed stays, hinges, or locks creating security and operation issues
• Poor weatherproofing: Gaps in seals allowing water and air infiltration

Window replacement costs £200-£800+ per unit depending on size and specification. Across a commercial building with 50+ windows, this represents substantial capital expenditure that must be factored into acquisition decisions.

5Electrical Installation Defects

Electrical systems in commercial properties deteriorate over time, creating safety hazards and operational failures. Our building surveyors identify electrical concerns in approximately 45% of commercial property inspections.

Common Electrical Issues:

• Obsolete consumer units: Old fuseboard systems lacking modern safety protection
• Insufficient circuit capacity: Inadequate provision for modern business equipment loads
• Exposed or damaged wiring: Safety hazards requiring immediate rectification
• Lack of RCD protection: Missing residual current devices on circuits serving equipment
• Failed emergency lighting: Non-functional egress lighting systems
• Outdated PAT testing: No evidence of portable appliance testing

6HVAC System Failures

Heating, ventilation, and air conditioning systems in commercial buildings are complex, expensive installations that require regular maintenance. My Commercial Building Surveyors frequently discover HVAC defects that affect operational costs and tenant comfort.

Typical HVAC Problems:

• Aging boilers: Equipment beyond economic repair requiring replacement (£15,000-£50,000+)
• Failed air handling units: Inadequate ventilation causing poor indoor air quality
• Refrigerant leaks: Air conditioning systems losing charge and efficiency
• Blocked or deteriorated ductwork: Restricting airflow and spreading contamination
• Controls malfunctions: Failed building management systems causing inefficient operation

Regular mechanical and electrical surveys by qualified building services engineers identify developing problems before system failures disrupt business operations.

7Asbestos Presence (Pre-2000 Buildings)

Approximately 70% of commercial buildings constructed before 2000 contain asbestos-containing materials (ACMs). While asbestos is not dangerous when undisturbed, it creates substantial liability issues and management obligations for building owners.

Common ACM Locations:

• Asbestos cement roofing sheets
• Pipe lagging and insulation
• Ceiling tiles and textured coatings
• Floor tiles and adhesives
• Electrical panel backing boards
• Fire doors and partitions

Legal Requirements:

The Control of Asbestos Regulations 2012 requires building owners to maintain an asbestos register and management plan. Our building surveyors identify suspected ACMs during inspections, recommending specialist asbestos surveys where materials are present. Asbestos removal costs £50-£200+ per square meter depending on material type and accessibility.

8Fire Safety and Compartmentation Issues

Commercial buildings must comply with fire safety regulations, yet our experienced team of surveyors regularly discovers fire compartmentation breaches and inadequate fire protection measures during building surveys.

Common Fire Safety Defects:

• Breached fire compartmentation: Service penetrations through fire-rated walls/floors without proper fire stopping
• Missing or damaged fire doors: Inadequate intumescent strips, failed closers, or propped-open doors
• Blocked fire escape routes: Obstructed egress paths or locked final exits
• Inadequate fire alarm systems: Insufficient coverage or expired service records
• Missing fire-resistant glazing: Standard glass in locations requiring fire-rated alternatives

Fire safety violations can result in enforcement notices requiring immediate remediation. My Commercial Building Surveyors identify these issues, allowing building owners to address problems before regulatory intervention.

9Drainage System Defects

Below-ground drainage systems are often neglected until failures occur. Our building surveyors recommend CCTV drainage surveys for commercial properties, frequently revealing serious defects in underground pipework.

Common Drainage Problems:

• Collapsed or fractured drains: Structural failure of underground pipework
• Root ingress: Tree roots penetrating and blocking drainage systems
• Incorrect falls: Poorly installed pipes causing standing water and blockages
• Defective inspection chambers: Damaged manholes allowing ground water infiltration
• Inadequate capacity: Undersized drainage for current building usage

Drainage repairs often require excavation and reinstatement costing £3,000-£15,000+ per defective section. Identifying problems through pre-purchase surveys allows cost negotiation or informed decisions.

10External Works and Car Park Deterioration

The external areas surrounding commercial buildings frequently show significant deterioration. My Commercial Building Surveyors assess car parks, access roads, boundary walls, and external lighting as integral components of commercial property assets.

Common External Defects:

• Failed tarmac surfaces: Cracking, potholing, or edge deterioration in parking areas
• Inadequate drainage: Standing water causing accelerated pavement failure
• Unsafe pedestrian routes: Trip hazards from uneven paving or defective surfaces
• Boundary security issues: Damaged fencing, walls, or access control systems
• Lighting failures: Non-functional external lighting creating security and safety concerns

Car park resurfacing costs £25-£60 per square meter. For a typical commercial property with 100-space car park (3,000m²), total replacement can cost £75,000-£180,000.

How My Commercial Building Surveyors Identify These Defects

Our comprehensive building surveys use systematic inspection methods combined with specialist equipment to detect defects that others might miss:

Visual Inspection Techniques

• Detailed examination of all accessible building elements
• Photography documenting every defect and area of concern
• Measurement and recording of crack widths and structural movement
• Assessment of repair quality and maintenance standards

Specialist Equipment

• Moisture meters: Identifying damp problems and water ingress
• Thermal imaging cameras: Detecting hidden defects, insulation failures, and moisture
• Endoscopes: Inspecting concealed voids and inaccessible areas
• Laser measuring tools: Accurate dimensional surveys and level checks
• Crack width gauges: Monitoring structural movement

Additional Investigations

Where our building surveyors identify significant concerns, we recommend specialist sub-contractor surveys:

• Electrical Installation Condition Reports (EICR)
• Mechanical and electrical systems surveys
• CCTV drainage surveys
• Asbestos management surveys
• Structural engineer assessments

The Value of Professional Building Surveys

Discovering these common defects through professional building surveys before purchase or lease allows you to:

• Negotiate reduced purchase prices: Reflect repair costs in your offer
• Require seller repairs: Make the transaction conditional on defect rectification
• Budget accurately: Plan capital expenditure for necessary repairs
• Avoid unexpected costs: No surprise expenses after completion
• Make informed decisions: Proceed, renegotiate, or withdraw based on factual evidence
• Plan maintenance programs: Prioritize repairs based on urgency and cost

Frequently Asked Questions

Are all building defects serious?

Not all defects require immediate action. Our building surveyors categorize issues by urgency—immediate safety concerns, necessary repairs (1-2 years), and longer-term maintenance items. This prioritization helps you allocate resources effectively.

Can I survey a building myself?

While building owners can conduct basic inspections, identifying defects requires professional training, specialist equipment, and technical knowledge. Insurance valuers, mortgage lenders, and legal advisors only accept reports from qualified RICS chartered surveyors.

How much does fixing these defects cost?

Repair costs vary dramatically based on defect severity, building size, and access. My Commercial Building Surveyors provide indicative cost estimates in our reports, helping you budget accurately. Typical commercial building defect rectification ranges from £20,000 to £200,000+ depending on issues discovered.

Should I still buy a property with defects?

Most commercial properties have some defects—the key is understanding their nature, urgency, and cost. Armed with accurate information from professional building surveys, you can negotiate fair terms that reflect the true condition of the property.

Conclusion: Protect Your Investment with Professional Surveys

These top ten building defects represent recurring issues our experienced team of surveyors identifies across thousands of commercial property inspections. Understanding common problems helps property owners recognize warning signs, but only professional building surveys by RICS chartered surveyors provide the comprehensive assessment necessary to make informed property decisions.

My Commercial Building Surveyors bring decades of combined experience to every commercial building survey. Our detailed reports document every defect, provide repair cost estimates, and recommend appropriate remediation strategies. This professional insight protects your investment, supports negotiation, and prevents costly surprises after completion.

Don't risk buying or leasing commercial property without understanding its true condition. Commission a professional building survey from our qualified team and gain the confidence that comes from complete property knowledge.