Buying a narrowboat is a big decision, and it's easy to get swept up in the excitement of finding "the one." But before you hand over any money, you need to ask the right questions. A good seller will answer these openly and honestly — and if they don't, that tells you something too.
Here are 30 questions every narrowboat buyer should ask, organised by category. Print this list, take it to viewings, and don't be afraid to work through every single one.
Hull and Structure (Questions 1-8)
- What's the hull thickness? Ask for the most recent ultrasonic hull survey results. New narrowboat baseplates are typically 10mm (6mm for sides). Anything below 5mm on the baseplate needs attention.
- When was the boat last blacked? Blacking (applying bitumen or epoxy paint to the hull below the waterline) protects against corrosion. It should be done every 2-4 years depending on the product used.
- Who built the hull and when? Some builders have better reputations than others. Knowing the builder helps you assess quality and find information about common issues with that build.
- Who did the fit-out? Was it a professional company, the previous owner, or a DIY project? Professional fit-outs from reputable companies tend to hold their value better.
- Is there any hull pitting or corrosion? Ask specifically, and ask to see any survey reports. Some pitting is normal on older boats but extensive pitting can be expensive to repair.
- Has any welding or steel repair work been done? If so, when, where, and by whom? Repair welds aren't necessarily bad — they can show a boat that's been well maintained — but you want to know the details.
- What condition are the anodes in? Sacrificial anodes protect the hull from galvanic corrosion. They need replacing periodically. If they're wasted away to nothing, the hull may have been less protected than it should be.
- Has the boat ever had any major structural work? Overplating, new baseplates, or significant repairs? This isn't necessarily bad but you should know about it.
Engine and Propulsion (Questions 9-15)
- What engine is fitted? Know the make, model, and type. Common narrowboat engines include Beta Marine, BMC 1.5/1.8, Lister, and Isuzu. Some are easier and cheaper to get parts for than others.
- How many engine hours? Engine hours are like mileage on a car. A well-maintained diesel with 3,000-5,000 hours is middle-aged. Over 8,000 hours, you should ask more questions about maintenance history.
- Is there a full service history? Regular oil changes, filter replacements, and belt changes are the basics. A folder of receipts and a service log is a very good sign.
- When were the belts last changed? Alternator and water pump belts wear out. If nobody knows when they were last changed, budget for doing it soon.
- What gearbox is fitted? Common types include PRM and Borg Warner. Ask if it's had any issues.
- What's the propeller condition? Has it been replaced or repaired? A damaged prop affects performance and fuel efficiency.
- Are there any engine leaks? Oil, coolant, or fuel leaks? A small weep might be minor, but significant leaks need investigating.
Electrical Systems (Questions 16-19)
- What battery setup does the boat have? How many batteries, what type (lead acid, AGM, lithium), and how old are they? Batteries have a finite lifespan — lead acid typically 3-5 years, lithium 10+ years.
- How is the boat charged? Engine alternator, solar panels, shore power, generator? What combination, and is it adequate for the owner's usage?
- Is there a 240V inverter? If so, what wattage? This determines what mains appliances you can run when away from shore power.
- When was the electrical system last inspected? Boat electrics can be a fire hazard if poorly installed or maintained. Ask if there's been a professional inspection.
Plumbing and Water (Questions 20-22)
- What's the water tank capacity? Larger tanks mean less frequent fill-ups. Typical range is 200-500 litres.
- What type of toilet is fitted? Pump-out, cassette, or composting? Each has different implications for daily life and maintenance.
- What's the hot water system? Calorifier heated by the engine, immersion heater on shore power, instantaneous gas water heater, or a combination? Does it work reliably?
Heating and Gas (Questions 23-25)
- What heating does the boat have? Solid fuel stove, diesel heater (Webasto/Eberspacher), gas heater, or a combination? If there's a stove, what condition is the flue in?
- When was the gas system last checked? Gas leaks on boats are extremely dangerous. The BSS covers gas safety, but ask specifically when the system was last inspected and by whom.
- How many gas bottles does it carry? Two is standard (one in use, one spare). Where are they stored, and is the locker properly ventilated and drained as per BSS requirements?
Paperwork and Legal (Questions 26-28)
- When does the BSS certificate expire? A current BSS is needed for a CRT licence. If it's due soon, factor in the cost of the examination and any remedial work.
- Is the CRT licence current? Check the licence is valid and matches the boat. How much time is remaining?
- Is insurance in place? While insurance won't transfer to you, knowing the boat has been insured is a good sign. Uninsured boats raise questions.
History and General (Questions 29-30)
- How many previous owners? A boat that's changed hands frequently might have issues that prompted multiple sales — or it might just be coincidence. Ask why each owner sold if possible.
- What would you want to know if you were buying this boat? This open-ended question sometimes prompts sellers to share things they wouldn't have volunteered otherwise. It's worth asking.
Bonus: What to Observe During the Viewing
Beyond the questions, pay attention to:
- Smell: Damp, diesel, or gas smells can indicate problems.
- Bilge: Is it dry, oily, or full of water? A small amount of clean water is normal. Oil or significant water isn't.
- General maintenance: Is the boat tidy and well-maintained, or are there signs of neglect?
- Fit and finish: Open cupboards, check behind panels where you can, look at the quality of plumbing and wiring.
- Start the engine: Listen for unusual noises, check for smoke, see if it settles into a steady idle.
Find Services and Surveyors
Need a surveyor or boatyard in your area? Browse our directory to find narrowboat services across the UK canal network.