Life Expectancy of a Canal Boat

We can all agree that the better you look after something, the longer it should last. Canal boats are no exception. When considering the life expectancy of a canal boat there are some common sense measures you can take to make sure it lasts, and also one or two factors which you might not be aware of. Let’s take a look at some of these now…

What is the Life Expectancy of a Canal Boat?

This might very well be one of those ‘how long is a piece of string’ questions… As we said at the start proper care will prolong a canal boats lifespan. Thinking about it logically, there are still canal boats happily pottering around today that were launched well over 100 years ago.

Whilst they may be legitimate centurions, the chances of all of their parts being the originals are slim. One could wonder, aside from the hull, how much of the original boat remains… And even then, the hull might have been plated and patched so many times that it is far from original.

That said, they reckon that the human body is entirely renewed on a cellular level every 7 years, and we are still all the same person, so let’s be true to the question and say at a maximum, provided you care for the boat, it is almost indefinite.

The lifespan of the boat depends largely on what it is constructed from. As a rough guess we can assume that around 90% of canal boats have steel hulls.

We are now going to tell you a couple of interesting facts regarding steel hulls.

Did you know that when steel Is submerged in water it slowly, on a molecular level, starts to release its atoms off into the ether? This process is called oxidisation. One of the reasons for blacking steel hulls is that it reduces the loss of these atoms. The speed of this process can greatly affect a hulls lifespan. A boat built 50 years ago may actually have lost up to 75% of its hull thickness through this process.

Surveyors are able to tell the thickness of a hull using ultrasound. If there is ever any doubt about a hull, have it surveyed before parting with your hard earned.

Something else which can affect a canal boats lifespan is the type of water in which it spends the majority of its life. Areas that have chalky deposits and soil (such as the South East of England) tend to deposit a layer of calcium on the hull. This acts as a sort of natural blacking and can reduce the oxidization of the metal. Conversely in areas that have a highly acidic water table, steel will degrade much quicker, due to a mild ‘electrolysis’.

There are some more modern boats which now use composites in place of steel. This may sound like an ideal solution at first, however it can be far from ideal in the wrong circumstances. Composites tend to be less durable than steel, and indeed a lot more expensive. One of the major downsides with composites is that when damaged they cannot be simply patched up. Fatigue and cracks are not an easy fix. So, what you gain in anti-corrosion capability, you may still lose monetarily if you have a prang or bump.

It should be obvious, but in order to prolong a boats lifespan you will need to maintain it regularly. Ideally once every couple of years it should be removed entirely from the water and re-blacked. Further to this, regular maintenance on things such as the engine and canopy will save costly bills further down the line.

If you are considering buying a boat it is worth considering how the boat has been used in the past. There is a school of thought that states that ex hire boats are a bad choice for purchase, due to the high likelihood that they have probably been roughly handled in one form or another. However, it pays to consider that hire boats will have been much more strictly maintained than a permanent residential narrowboat. Ultimately a survey is perhaps the best way to ascertain how ‘good’ a hull is.


Provided a boat is well maintained there is almost no limit to its lifespan. The life expectancy of a canal boat depends solely on how well it has been cared for, and provided it is well looked after, you could realistically expect it to outlive its owner, as a great many have done.

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