Could this be the shape of things to come?
SINCE the birth of the waterways, there haven’t been that many alterations to the design of narrowboats; minor adaptations and trends have come and gone but the basic design hasn’t undergone any significant changes.
But that may be about to change. Over the past few years, prompted by the need to produce more efficient boats to help reduce fuel use and emissions, a number of designers have come up with what they feel to be improvements.
One of these is Simon Boyde, MD of Cadal Craft, based in Leicestershire. Simon is a qualified naval architect and AssociateMember of theRoyal Institute of Naval Architects. He first took to the inlandwaterways as a teenager during extended family holidays and, until recently, had been based inHongKong, where he ran Storm Force Marine Ltd – amarine distribution business.
But in 2021, he relocated back to the UK and set up Cadal Craft Ltd to make full use of his design andmarine engineering experience and many years as an inland waterways user. He intends to produce an alternative to the current ‘high drag, low draught, inefficient hull designs’.
The result was the recent launch of Cadal’s prototype boat, a 60ft cruiser stern narrowboat that is UKRCR Cat C, heat pump ready and suitable for tidal waters. The design uses a deeper draught hull, which by keeping the boat level-trimmed, in fact, has a lower navigational draught than most current designs. This should not only allow owners to explore new areas safely, including tidal rivers, but while doing so, reducing their impact on the environment.
The new design uses a low-drag hull designwith an elongated bowand stern swims to reduce pressure waves. The double chine hull also is designed with a reducing beambelow the cabin sole, an area used for pipework and tanks. Reducing the beam, according to Simon, also reduces the ‘blockage factor’, a principal contributor to drag on a confined waterway. This is just one example of the level of detail used in the design.
With the main aim of producing a low-impact boat, the focus must also be on heating. With a large number of boats using solid fuel, which is both inefficient and polluting, Cadal Craft’s focus has extended to the boat’s heating system. The company’s studies have found that using radiators fixed to thin steelwalls is far fromefficient. The hull wall inevitably radiates heat both ways – into the boat and out of the boat – which is very inefficient. Instead, they use awater source heat pump towarm air to heat the boat’s occupants.
To this end, Cadal Craft has a patent pending hull integrated structural heat exchanger. With a hybrid engine installed, the company has also looked to utilise the heat fromthe diesel engine when in use. This somewhat complex system has been developed with a company called Frigomar. The result is a system that is both efficient and dramatically reduces pollution.
Although not intended as an example of the finished product, the prototype allowed Simon to iron out any issues with the design and construction. It has also allowed potential buyers to see the design elements. Although Cadal is not looking to become a volume boat builder, the company provides a design and consultancy service and supplies hulls to boat builders who will then fit out to the client’s specific requirements.
Cadal’s approach to the design of narrowboats isn’t restricted to the hull and its action under way. Simon has also addressed areas such as heating and ventilation. Cadal has looked into not only the design of its boat but also its construction.
The quality of the steel used and the competence of the fabricators is something Simon feels is vitally important, given thatCadal is looking to sell hulls at various stages of completion.
Under way the boat is, as you might expect, quiet, given that we used the electricmotor to take us a short distance up the GU to Foxton Locks. Despite the blustery conditions, the boat held its line well and was easy to manoeuvre. What was very noticeable was the lack of movement of the moored boats that we passed. This is due to the low-drag hull design and the lack of wash.
As for costs, it is difficult to give a final price on the cost of a boat from Cadal due to the wide range of variations and stages of finish and the company acknowledges that its hulls will not be the cheapest on themarket, but certainly not the most expensive.
Considerable time has been spent in finding what Cadal feels to be the best fabricators to produce the hulls the company supplies. Although almost impossible to quantify, the increased efficiency of the boat, resulting in a reduction in the amount of fuel being burnt, will go some way to offset the higher price.
More naval architects are entering the marketplace offering to improve existing designs, a fact borne out by the number of those exhibiting at Crick. But that is a good thing. With the need to make the most out of every bit of fuel used for financial and environmental reasons, it is good to see newideas and innovations being tried.
Cadal Craft will be exhibiting in the inland zone at BoatLife Live in February.