n.b. Whisper

Technical Design

had spent eighteen years as a twinkle in the eye (ever since I took a narrowboat holiday on the Shropshire Union Canal as a student in 1979) and finally took physical form and reality in the winter of '98/'99. A number of fundamental design decisions underpinned her final specification, the most significant being:

  • Gasless
  • Extremely quiet operation
  • "Go anywhere" dimensions
  • Facilities for extended cruising and working on-board
  • Comfortable winter cruising
  • Maximum space utilisation
These all came about as the result of extensive cruising over a number of years on hire boats, a "family" boat and boats loaned by friends. You can find some details about design innovations and good ideas incorporated into Whisper here.

The plan on the right shows the layout of
Whisper. Starting from the stern (top): Counter with access hatch to weed hatch, central heating boiler and storage. Steerers position with fold-down seat for companion. Hatch is enlarged to accommodate seat.
Also housed in this compartment, which acts as a wet locker and general storage area are the engine controls, electrical panels (12v and 230v AC), Inverter (Mastervolt Dakar Combi) and calorifier.

Through two half-doors to the office area with desk and chair to port, storage to starboard. Through the internal security door (which also acts as the bed headboard when closed) to the bedroom/engine room! The Beta PropGen, a toilet holding tank and a toilet flushing water tank are installed beneath a permanent base which extends sideways across the companionway at night to form a full width double bed. Over the foot of the bed is a houdini hatch. At the foot of the bed are a TV shelf, drawers and a 2/3 width wardrobe.

Forward of this is the bathroom, which is full width and can be closed off at both ends for privacy. The double shower with glazed sliding door and its own solar extractor vent is to the port opposite the vanity basin and storage. Next to the shower is the separate WC with its own door for privacy (an another solar extractor fan) during the day.

The utility room is next along the port side (its door doubles as the forward bathroom door) and houses a washing machine and condensing tumble dryer. Opposite is more storage and shelving incorporating the microwave.

Immediately forward of this is the galley which is equipped with a full-size refrigerator on the port side and an electric double oven and induction hob (with powered extractor fan above) and studio dishwasher to the starboard. A second houdini hatch provides extra light and ventilation.

The breakfast-bar style worktop is positioned opposite the double side hatch. Forward of this is the saloon area with free standing furniture. Shelving and a TV/Hi-Fi unit are built-in to the port side by the forward cabin doors and the stove sits above a large coal drawer to the starboard side.

The front well deck houses a stainless steel water tank below and has lockers/seats either side. The cratch board is fixed but fully glazed and the top board is hinged so it can be opened out onto the cabin roof. The front locker provides storage as well as acting as a chain locker for the anchor.

The two rear compartments form a 'secure area' accessible only via an internal security door and the external steel rear doors with security locks. This section has portholes only. All window glass is high security laminated and all locks are 5-lever or above.


First of all, I have nothing against bottled gas per se! It is often a very cost effective and convenient heating and cooking fuel, and it has been present on every boat I've ever cruised on. However, despite the availability of good gas detectors, I am uneasy about living, and especially sleeping, in a partially submerged steel container that also houses gas pipes and appliances, with nowhere for leaking gas (or worse, carbon monoxide) to go but into the bottom of the boat (it being heavier than air). Second, gas bottles are heavy and cumbersome, and the potential for gas leaks at every changeover is always there. Third, because of the perceived danger of gas installations, the regulations applying to installations and appliances become more severe almost every year. At the least this results in increased inspection and certification costs, and at the worst may result in the condemnation and scrapping of the installation or of individual appliances at some unspecificed point in the future.

There are two practical alternatives to gas heating and cooking. Diesel or electric. Heating with the former is a well established method on modern steel narrowboats and consequently Whisper is equipped with an Eberspacher diesel-fired boiler supplying a calorifier tank and skirting radiators. Cooking, however, is a little more problematic. Diesel-fired ranges have been around for a number of years in domestic kitchens but can be a little too bulky for boat use. They are also best left on a low setting all the time, which at the height of summer in a narrow steel box is not a particularly good idea! A number of diesel-fired cookers (oven and hob) have recently come onto the market, but they are something of an unknown quantity at the moment, being almost totally unheard-of in domestic kitchens. Electric cookers on the other hand, are well known in this context, whilst being almost completely unheard-of on boats! Certain types of electric hob are known to be as controllable as gas, and electric ovens tend to be favoured over gas ones anyway. The fundamental problem with electric cooking is getting enough electrical power on board to make it a realistic proposition. Solve this, and the rest, as they say, is plain sailing!

The solution to this (and the next point regarding quiet operation) is the Beta Marine PropGen unit. This is a 4 cylinder 2.2 litre diesel engine and directly coupled 11.3Kw generator, in a noise reducing cocoon. Since the average hob and oven each require around 5Kw at maximum power this just does the job comfortably, with power to spare.

The electric hob on Whisper is a De Dietrich Induction hob, which heats the base of the pans directly via electric induction - the hob surface itself does not heat up, making the hob surface a much less dangerous place for stray hands in the confined space of the galley. It is also the most efficient form of electric hob cooking, with the added advantage that power is only consumed when the pans are actually on the surface of the hob.

Extremely quiet operation

After many days cruising, standing directly above, or near to, a normal diesel engine, with the noise of the engine ringing in my ears for hours afterwards, I know that I want a very quiet propulsion system!

There are a number of ways of achieving this. The two main sources of noise from a conventional diesel engine are the moving parts of the engine itself and the exhaust outlet. Both of these can be addressed to a lesser or greater extent. Soundproofing engine compartments and fitting anti-vibration mounts is simple and relatively effective. A good silencer (the so-called 'Hospital Silencer' being the most effective example) also helps greatly. The simple expedient of not placing the engine near to or underneath the steerer can significantly enhance the cruising experience!

More radical solutions include alternative motive power units such as steam or electric. The former is extremely quiet and pleasurable (from my experiences steering the former ice-boat Laplander) but the installation and management of a steam engine is a labour of love that I personally do not want to get into! Pure electric power is becoming more popular in areas where charging points can be provided, such as the Broads, but they are almost unheard-of on the main waterways network. The main drawbacks are the large battery banks required and the need to moor at designated charging points overnight. Renewable energy sources such as wind and solar power just don't have the capacity to provide sufficient power for regular cruising. Hybrid systems such as diesel-electric avoid the charging, generating and mass storage problems but bring you right back to the issues associated with quietening a diesel engine. At least with these systems the diesel is usually constant speed, making soundproofing or other noise reduction strategies more effective. Also, with diesel-electric installations the engine can typically be smaller (and therefore a little quieter) than a conventional diesel engine for the same size boat.

For reasons discussed in the previous section Whisper is actually powered by a Beta Marine PropGen diesel engine with a heavy duty generator. However, the PropGen has several advantages over a conventional diesel engine. First and foremost, it is constant running (at 1500 rpm), making it easier to select effective soundproofing materials. Second, it is cocooned, along with the generator and gearbox, in a highly effective soundproof enclosure. Third, it has been positioned some 12 feet away from the steerer and has an exhaust system whose outlet is also 10 feet away below gunwhale level. Fourth, the exhaust system itself contains a completely enclosed Hospital silencer. Finally, the selection of a constant running diesel engine makes the addition of an Active Noise Reduction ("anti-noise") system in future a realistic possibility (when the technology matures and becomes more widely available).

"Go anywhere" dimensions

In terms of beam, there is no question. If you want to be able to cruise the entire English and Welsh system it must be 6'10", the usual beam of a "narrowboat". Any wider than this and you are restricted to either the northern wide canals and rivers or the southern wide canals and rivers (including the Thames). With the narrow midland network between, never the twain shall meet!

With the recent lengthening of the locks between the main system and the Middle Levels the shortest locks on the connected system are now the broad 58'6" locks of the Calder & Hebble Navigation in Yorkshire. Almost everything else is 60' and above. However, since the C&H locks are broad a 60' narrowboat will just fit diagonally (whilst this is not water resource friendly, it is rare for there to be a water shortage problem on this waterway) so, given that every foot of extra space is precious, Whisper has been built to a length of 60'.

Air draft for narrowboats is not normally an issue (except at Froghall Tunnel and the 100 yards of the Caldon Canal beyond), save for roof-mounted features such as chimneys and aerials which must, of course, be de-mountable.

Facilities for extended cruising and working on-board

Whisper is not designed to be a residential boat (a term which has a strict legal and licencing meanings amongst other things). However, to fulfil the needs of an extended cruising boat it requires many of the same facilities and home comforts. Consequently, Whisper is equipped with a full range of domestic appliances such as an automatic washing machine and separate dryer, as well as the fully electric galley oven and hob (oh, and a small dishwasher for when we're feeling really lazy!).

The water and holding tanks have been designed to be as large as is practicable to maximise the duration between filling and/or emptying. The 85 gallon stainless steel water tank is augmented by a separate 75 gallon toilet flushing water tank which provides trim balancing for the 90 gallon toilet holding tank. The latter should allow for full use for two people for 20+ days before requiring a pump-out (the electric flush toilet requires only half a gallon or less per flush).

Where would we be without a living to earn! All I need is a small office, a computer and a cellphone connection to the internet. The PropGen unit ensures that there is an adequate supply of electrical power, and a permanent "car-kit" style phone installation with an external aerial provides an effective connection. The external aerial makes a tremendous difference to signal strength and therefore reception, rendering most locations on the waterways network accessible to cellphones.

Silent operation at a mooring for an extended period is important to me. Whilst the PropGen is quiet, I'd rather not disturb the peace at all, if possible. So it will only be used when necessary. A bank of four 220Ah domestic batteries supplies the normal power requirements of Whisper for a considerable time before a recharge is required. Both 12v DC and 230v AC circuits are available, the latter using a 2.5Kw true sine-wave inverter (Mastervolt Dakar Combi) so that any domestic electrical equipment can be accommodated.

Comfortable winter cruising

One just has to accept that with a narrowboat, the steerer is going to get cold and wet in winter! However, that doesn't mean that you should be cold or uncomfortable once moored. Whisper is equipped with diesel-fired central heating (and also water heating) and is insulated to a high standard with urethane foam. As a back-up, and because I like a real fire now and again, the saloon is equipped with a solid fuel stove, and there is plenty of solid fuel storage in the forward locker (where the gas bottles might have been!).

In lieu of a boatman's stove in the rear cabin (for which there was insufficient room) the steerer can be warmed on cold days by the addition of an electric fan heater powered directly by the PropGen. When cruising there's plenty of electrical power to spare.

Maximum space utilisation

This almost goes without saying, but there are certain design decisions which have an effect. A "trad" stern certainly provides the most enclosed space, and the traditional boatman's cabin is certainly as space-saving as it gets, if you like or need that sort of thing, but an engine room is a luxury on a 60' boat that can be ill-afforded if you don't have a nice chunky vintage engine to show off! Consequently, the engine on Whisper has been placed under the fixed bed (see diagram at top of page), along with the flushing and holding tanks. This is less of a problem than it first appears, because with the PropGen in its acoustic, sealed cocoon there is very little convected or conducted heat, no smell, and noise and vibration are not real issues unless you happen to want to cruise and sleep at the same time!

The front cockpit, otherwise useless in wet or cold weather is made an adjunct to the boat interior by the use of a full cratch board and cratch cover. The cratch board is fixed, but glazed for forward viewing, and the top plank, with cratch cover attached) is hinged to allow the cockpit to be opened out on warm days.

It's the little things that count too: the solid fuel stove has been stood on a plinth containing a drawer capable of taking a full 25kg bag of coal. This utilises otherwise dead space and does away with the need for a coal scuttle or bucket of some kind. The saloon has no fixed furniture, allowing maximum flexibility, but the need for a table has been eliminated by the extending "breakfast bar" style galley worktop. There is no companionway as such down one side of the boat. The bathroom utilises the full width of the boat and can be closed off at either end. A double shower replaces the usual small bath to economise on water. The bedroom similarly utilises the entire width of the boat to provide a 5' 10" by 6'6" bed.