CCTV Drain Survey – Complete Guide
Everything you need to know about drain camera inspections: what they reveal, when you need one, and how to interpret reports.
What is a CCTV drain survey?
A CCTV drain survey uses specialist waterproof cameras mounted on flexible rods or crawlers to inspect underground drainage pipes from the inside. The camera transmits real-time video to operators above ground, allowing them to identify defects, blockages, and structural issues without excavation.
Modern surveys use high-definition cameras with powerful LED lights, capable of inspecting pipes from 50mm to 2000mm diameter, typically covering depths up to 100 metres.
When you need a CCTV drain survey
Property purchase (pre-purchase surveys)
Many mortgage lenders and insurers now require drainage evidence before completion. A survey reveals hidden problems that could cost thousands to fix later:
- Root ingress: Tree roots penetrating joints or cracks
- Collapsed sections: Pipe failures requiring excavation
- Poor installation: Incorrect falls, misaligned joints, or substandard materials
- Shared drains: Confirming responsibility boundaries with neighbours
Recurring problems
If you experience repeated blockages, slow drainage, or foul smells despite clearing attempts, a CCTV survey identifies the root cause:
- Offset joints allowing debris accumulation
- Bellied sections (sags) where waste collects
- Scale build-up or fat deposits restricting flow
- Structural cracks allowing soil infiltration
Insurance claims
Essential evidence for drainage-related insurance claims. The video footage and condition report provide:
- Visual proof of damage (sudden vs. gradual deterioration)
- Defect location and severity grading
- Repair cost estimates
- Evidence of proper maintenance (or lack thereof)
Planning & building work
Before extensions, loft conversions, or new connections, surveys confirm:
- Current drain routes and depths
- Capacity for additional load
- Connection point suitability
- Whether existing systems meet Building Regulations
What a CCTV survey reveals
Structural defects
- Cracks & fractures: Longitudinal or circumferential breaks in pipe walls
- Collapsed sections: Complete pipe failure requiring excavation
- Displaced joints: Sections pulled apart or misaligned
- Deformed pipes: Crushed or distorted by ground movement or traffic loading
Blockages & restrictions
- Root intrusion: Fine roots through joints or heavy matting blocking flow
- Fat & debris build-up: Solidified fats, wipes, sanitary products
- Scale deposits: Calcium or mineral accumulation reducing diameter
- Incorrect installations: Pipe reducers, sharp bends, or back-falls
Connection & design issues
- Illegal connections: Surface water to foul, or vice versa
- Missing branch connections: Capped or abandoned laterals
- Poor falls: Insufficient gradient causing standing water
- Bellied sections: Dips in the run where solids settle
Understanding survey reports
Condition grading (WRc standards)
UK drainage surveys use a standardised 5-grade system:
- G1 (Good) – No defects, normal operation
- G2 (Fair) – Minor defects, monitor but no immediate action
- G3 (Poor) – Defects requiring attention within 12 months
- G4 (Bad) – Urgent repairs needed, potential for failure
- G5 (Collapsed) – Immediate action required, excavation necessary
What you'll receive
- Video footage: Full inspection run (usually 30-60 minutes)
- Still images: Key defects with annotations
- Written report: Defect descriptions, grading, and locations
- Drain mapping: Scale drawings showing routes, depths, and access points
- Recommendations: Repair options, urgency, and estimated costs
Interpreting results
Focus on:
- G4/G5 defects: These need immediate attention
- Root patterns: Fine hair-like roots indicate potential for heavier ingress
- Multiple defects in one area: May indicate localised ground movement
- Standing water: Could mean poor falls or a downstream blockage
Survey costs & what's included
Typical UK pricing (2025):
- Basic survey (no report): £80-£150 – Video review on-site, verbal findings
- Standard survey + report: £150-£250 – Video, images, written report
- Full survey + mapping: £250-£400 – Complete documentation including CAD drawings
- Specialist surveys: £400+ – Large diameter pipes, long runs, or difficult access
Prices vary by region, property size, and drain length. London and South East typically 20-30% higher.
What affects the cost?
- Property type: Flats cheaper than detached houses with multiple drain runs
- Access difficulties: Lifting paving, confined spaces, or high-level connections
- Drain length: Most quotes cover 30-50m; longer runs cost more
- Pre-cleaning: Heavily blocked drains may need jetting first (£80-£150 extra)
- Report detail: Full engineering reports with recommendations cost more than basic footage
Survey process: what to expect
- Access point identification (15 mins): Locate manholes, inspection chambers, or rodding eyes
- Pre-cleaning if needed (30-60 mins): Jetting to clear debris for clear camera view
- Camera insertion (45-90 mins): Systematic inspection of all accessible runs
- Defect logging (ongoing): Operator notes defects, measures distances, captures stills
- Report compilation (1-3 days): Video editing, mapping, written recommendations
Total on-site time: 1-3 hours depending on property size and drain complexity.
After the survey: next steps
If defects are found
Your options typically include:
- No-dig repairs: Patch lining for cracks/joints (£400-£1,200 per repair)
- Full pipe lining: Creates new inner pipe skin (£80-£150 per metre)
- Targeted excavation: Dig and replace collapsed sections (£1,000-£5,000 depending on depth/access)
- Root cutting: Mechanical removal with maintenance plan (£150-£300, then annual)
For property purchases
Use the report to:
- Negotiate purchase price reductions (£3,000-£10,000 typical for major defects)
- Request seller completes repairs before exchange
- Budget for post-purchase drainage works
- Inform your buildings insurance of pre-existing conditions
Frequently asked questions
How long does a CCTV survey take?
1-3 hours on-site depending on property size and number of drain runs. Reports typically delivered within 3-5 working days.
Can surveys be done in the rain?
Yes, though heavy rain can limit visibility if drains are actively flowing. Best results in dry conditions.
Will the survey damage my drains?
No. Cameras are non-invasive and designed to navigate bends and junctions without causing damage.
Can surveys inspect septic tanks?
Cameras can inspect inlet/outlet pipes and internal baffles, but tank condition assessment usually requires physical inspection and emptying.
Do I need to be present?
Not essential if contractors have access to manholes/chambers. However, being present for the live feed helps you understand findings immediately.
How often should drains be surveyed?
Preventative surveys every 5-10 years for older properties, or when problems occur. Commercial properties may require annual inspections.