Richardw's Narrow Boat Project -BILGE AND BALLAST

Discussion in 'Metal Boat Building' started by richardw66, Nov 27, 2013.

  1. peter radclyffe
    Joined: Mar 2009
    Posts: 1,454
    Likes: 72, Points: 58, Legacy Rep: 680
    Location: europe

    peter radclyffe Senior Member

    why not use adhocs design, he is one of the best naval architects in the world
     
    1 person likes this.
  2. michael pierzga
    Joined: Dec 2008
    Posts: 4,862
    Likes: 116, Points: 0, Legacy Rep: 1180
    Location: spain

    michael pierzga Senior Member

    And a canal boat has a keel ?
     
  3. richardw66
    Joined: Nov 2013
    Posts: 47
    Likes: 2, Points: 0, Legacy Rep: 10
    Location: Rugby / London

    richardw66 Junior Member

    Thank you all very much for you inputs, they are much appreciated. I did come into this project with ideas gained from the construction industry with the aim that a few could transfer over and resolve many generic problems that inherent with the way Narrow Boats are constructed and fitted out.

    I've learnt a lot about ballast as discussions have progressed and I can now see there are many different facets to address. The idea I am about to show is how we do it in the construction industry which I have to say over recent years regulations and materials have changed immensely when it come to CO2 emissions and insulation and at the same time the work force behind it has become somewhat de-skilled. I don't know why but from my perspective the Narrow boat industry has become set in its ways and has been for many years and I just think as an outsider there must be a better way. I may be wrong but the way I'm going about it is to take a new ground up approach and question everything that has been done before, but now I'm bragging so why don't I just show my hand and you all give me your honest opinions.

    Remember this will be a Home, not just a live aboard narrow boat, quality and longevity are as much important just as if it were a house.

    Onwards: I prepared the following sometime ago and since then my understanding has changed so may be parts of it need to also, I'll let you be the judge...


    Ballast and Bilge.

    On a boat with a V shaped keel you need the inner floor to be level so the space left over underneath is called the bilge but why would you need a bilge on a flat bottomed boat? Somewhere for any water to drain to or somewhere to place the ballast might be good answers but do you really want water in the bottom of your boat and is that the best place to put the ballast? Why carry around a load of old bricks and concrete blocks that have absolutely no other use whatsoever? Going back to my F1 mind set I keep bragging about the best solutions are those that have more than one advantage. I'm talking about a component having a 'Primary Use' and then having at least one other inherent or incidental 'Secondary Benefit'. Take ballast for instance, it is just dead weight or Mass; yes concrete slabs provide mass but they serve no other useful purpose.

    Staying with the word 'Mass' let's put the word 'Thermal' in front of it and now we have Thermal Mass. If we could heat the concrete blocks up with otherwise waste heat from the engine then they would store the heat and release it slowly into the interior. Think about it, if you heat air it quickly loses its heat afterwards because it is thin and cannot hold onto heat. Heat water and it retains the heat longer because it is thicker than air. Now concrete is thicker than water; see where I'm going with this? ...

    There's how the system will work: we need ballast and in winter at least we also need heat and to keep in the heat we will also need insulation so why not combine all three? Instead of laying concrete slabs in the bottom of the shell why not lay say 100mm of Kingspan K15 Rigid Insulation (the best!), followed by a 5mm thick Etherfoam resilient layer to improve the boat acoustics, followed by the installation of proprietary under floor wet heating system such as Rehau. Then top it off and to encapsulate the pipe work pour in a self levelling screed such as 'Gyvlon' to a depth of 45mm making a total makeup thickness of 150mm.

    Heating the water is the easy bit, there are loads of ways to do that and the advantages are obvious; every square inch of the boat is heated from the bottom upwards including cupboards and storage spaces helping to keep surfaces well above the dew point temperature and vastly reducing the chances of condensation forming; I'll write more about condensation and it's opposite, ventilation later.

    For now our lateral thinking has resulted in components that have a primary, secondary and tertiary use so surely that's the way to go.

    And as those annoying sales ads say, But wait! There's more! If we go back to the traditional make up there would have been a plywood floor on top of timber battens that sat on top of steel angle baseplate stiffeners and if we're lucky a bit of expanded polystyrene underneath. Now we don't need any of that or need to use an angle section for the stiffeners because we don't need the top face as the weight of our 'floating screed slab floor' will be uniformly spread across the insulation so we could use flat sections as stiffeners which are cheaper or if our baseplate was 15mm thick one could argue that we don't need them at all. (Or do we? What about the knees? How will those be braced if there are no stiffeners?).

    The thing about a narrow boat is there is not much floor area so one can really go to town on floor finishes by buying bargain end of lines and leftovers off eBay. Picture this; a nice warm under bare feet limestone tiled floor in the salon, black slate in the kitchen, tumbled travertine in the bathroom and a black and red check quarry tile floor in the boatman cabin and engine room. As for the engine itself I would shutter that area off and pour a lower slab without insulation but on top a material called Regupol which will effectively mean the engine will sit on its own isolated floor slab and not transfer any vibration through the rest of the boat, clever eh? Now what other narrow boats do you know that have that level of floor insulation and heating? Would you still prefer bare wood boards or cheap laminate floors in your new boat now?


    Going back to the notion that a bilge is somewhere for water to drain to; with this concept if there was water inside the bottom of your boat you would soon know about it because it will be on the floor and you'd mop it up. How it got there would be a different matter but if I thought the boat was going to leak I would seal the inside before the insulation went down with a high-performance single ply liquid applied roofing membrane such as a Kemper System and then it won't leak ever, period.

    Of course there still will be a very small accessible and baffled bilge right at the back of the swim where the prop shaft goes though just in case a little bit of water comes in. The best way to do that will be discussed on another thread.
     

    Attached Files:

  4. michael pierzga
    Joined: Dec 2008
    Posts: 4,862
    Likes: 116, Points: 0, Legacy Rep: 1180
    Location: spain

    michael pierzga Senior Member

    Dont know what im looking at and not sure what you are talking about.

    Steel needs air flow. A bilge must be open , ventilated and accessible.

    The cabin sole can be your choice of material.
     
  5. SukiSolo
    Joined: Dec 2012
    Posts: 1,269
    Likes: 27, Points: 0, Legacy Rep: 271
    Location: Hampshire UK

    SukiSolo Senior Member

    Water WILL get in underneath a concrete or different material screeded into the hull bottom. Partly from differential expansion/contraction of materials partly from corrosion at the edges. You will not avoid water on the inside of the hull as Michael says you need good ventilation to minimise its impact over time. One's own breath creates quite a bit of condensation and that of several people can give dripping ceilings...well cabin roof interiors. Ventilation is key, far far more than a house.

    There is nothing wrong with your other ideas as long as you can keep headroom acceptable. It would be good to be able to pull the floor up to inspect the hull periodically so an underfloor heating solution would have to accomodate this. It could be sectionised and still moveable ie light enough.
    That alone would be revolutionary to the narrow boat industry but quite doable. Pivoting panels maybe?


    The stern and motor with prop gland will have to have a dedicated area or areas for water leaking in and an oil sump tray etc anyway. The less other stuff in that area the better. Most inboards are mounted on bearers which are a direct connection to the hull. Whether using an AV mounting system is a good idea with a fixed propshaft and gland/stuffing box etc I'm not sure. Maybe if the engine is very smooth (ie counterbalanced) and/or the drive might be hydraulic you could nearly fully isolate the vibration. Some on here will know more about this, but most diesels used on canal boats are rated at 2,500 hrs + for life. I've yet to be in any boat that is diesel powered where you could not feel and hear the throb....though some are a awful lot better than others. You may also need space for hand crank starting too.

    A much more radical solution would be a wood pellet powered steam engine! Much quieter and smoother, but I grant a lot more space required for the pellets, than diesel.

    So a few more considerations.

    Michael, the traditional narrow boats are quite flat (both planes) with no keel. Some may have a vestigal spine/keel/hog but more the ancient wooden ones. The bows rise in a V shape with usually a reinforcing part at the front of the joint resembling a thin keel. There is a bit of construction variation.
     
  6. richardw66
    Joined: Nov 2013
    Posts: 47
    Likes: 2, Points: 0, Legacy Rep: 10
    Location: Rugby / London

    richardw66 Junior Member

    My own research has discovered that original and therefore older locks were built 7ft 6in wide and the boats 7ft wide. Over time some of the lock walls have deformed and bellied inwards and likewise some of the older boats have sagged outwards so it can be a very tight fit. The newer locks are wider at 14ft wide which also includes the shortest 58ft long lock so I am informed that a 62ft boat can be shoehorned in diagonally.

    To give a bit of clearance it is now recommended that the new boat construction should have a beam 6ft 10in. The air draft should be a maximum of 6ft and the draft be as deep as you dare! I live in Rugby in the Midlands and local canal locks are bellied and narrow. I have a friend who has a boat with a 2ft 6in draft and you can feel it on the tiller dragging along the bottom of the cut. I am aiming at a draft of 2ft which will result in an air draft of 5ft 3in and have at least 6ft 6in of internal headroom.

    As for the bow and stern design; I'll start a new thread on that subject in due course.
     
    calevi likes this.
  7. richardw66
    Joined: Nov 2013
    Posts: 47
    Likes: 2, Points: 0, Legacy Rep: 10
    Location: Rugby / London

    richardw66 Junior Member

    By the way, for all the foreigners who might h not understand our antiquated imperial system of measurement; an Inch is 25.4mm and there are 12 inches to the foot, so work it out!

    Actually I'm of that age where I am bilingual so use an switch between the both. Especially back in my old formula 1 days where we used metric millimetres but if we wanted to really precise we used inches! I'm talking thousandths of an inch of course expressed as a decimal because it was far easier to envisage what a thou was as apposed to 0.025 of a millimetre; Fag Papers were a thou thick for a start.
     
  8. michael pierzga
    Joined: Dec 2008
    Posts: 4,862
    Likes: 116, Points: 0, Legacy Rep: 1180
    Location: spain

    michael pierzga Senior Member

    You need to first sketch and post.

    With this be an Urban Cruiser ?

    A classic, a modern ...

    [​IMG]


    [​IMG]
     
  9. SukiSolo
    Joined: Dec 2012
    Posts: 1,269
    Likes: 27, Points: 0, Legacy Rep: 271
    Location: Hampshire UK

    SukiSolo Senior Member

    Quote

    'What is a house but a badly built boat'

    Not sure who said it, maybe Uffa Fox but it still rings true.

    Actually I use mm almost all the time including thousand'ths of. It is just the toolmakers who still insist on sodding imperial, well not all of them. Last set of decimal inch drawings I did was in 93 for a US company...thank goodness for one click CAD conversion.. SI units are generally far easier despite what the 'Keep the pound' lot think.

    Nice one Michael, I think Richard will be going modern classica with a modern twist, and it ought to work.

    Shame they didn't build the locks 25' wide+ but I suspect the water supply and places like the 8 lock drop/raise Foxton? near Leicester would certainly have needed an awfully large reservoir for that.
     
  10. richardw66
    Joined: Nov 2013
    Posts: 47
    Likes: 2, Points: 0, Legacy Rep: 10
    Location: Rugby / London

    richardw66 Junior Member

    Nice pictures and a very good question.

    I very much think it will be a 'typical' from the outside at least English Narrow Boat for use on the UK Inland Waterways otherwise know as Canal or what us Brits sometimes refer to as 'The Cut'

    It goes back 200 years so there is a lot of tradition but what Id like to do is break the mould and achieve is a mixture of both. I'd love to do something like your images but I think that would be more like smashing the mould rather than just breaking it!
     
  11. richardw66
    Joined: Nov 2013
    Posts: 47
    Likes: 2, Points: 0, Legacy Rep: 10
    Location: Rugby / London

    richardw66 Junior Member

    Oi! I heard that! I was a Toolmaker once upon a time!
     
  12. waikikin
    Joined: Jan 2006
    Posts: 2,440
    Likes: 179, Points: 73, Legacy Rep: 871
    Location: Australia

    waikikin Senior Member

    Thanks for the info Peter, it seems that Waterways world may need to chase some advertising, I'd suggest from Promite(makes the consumer more adaptable & intellegent), if I ever sell a Narrow Boat into the English market I'll ballast with Vegemite, great source of vitamin B for the morning after the pub & makes for a "happy little Narrowow Boat"
    Jeff.:cool:
     
  13. Ad Hoc
    Joined: Oct 2008
    Posts: 7,788
    Likes: 1,688, Points: 113, Legacy Rep: 2488
    Location: Japan

    Ad Hoc Naval Architect

    Just about :)

    Dutch Barge Fwd WLs.jpg
     
  14. SukiSolo
    Joined: Dec 2012
    Posts: 1,269
    Likes: 27, Points: 0, Legacy Rep: 271
    Location: Hampshire UK

    SukiSolo Senior Member

    Very sweet lines, Ad Hoc for that type of vessel. Thank you very much for sharing. Always a bit of fun trying to get chines to give something close to the ideal or ones vision of ideal!. Nice panel shaping to get close to those lines.

    Hope Richard takes that form on board, as normal narrow boats are very bluff and create a lot of disturbance along the canals. This damages the banks and silts up the waterway, somewhat self defeating. The form you have shared would be far less damaging to that environment at the speeds concerned.
     

  15. Simonosteopath
    Joined: Jul 2014
    Posts: 11
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: Surrey

    Simonosteopath Junior Member

    Hull needs air?

    Hi Michael
    I posted a response to this area on Richardw66's other thread but it's worth repeating here too:-

    This lack of insulation also gets me! Here, for what it's worth, is my view on why it now should be and also why it isn't.

    Why it isn't:-
    Traditionally, old insulation materials used to be absorbent and could also 'breath', ie, they were not air-tight. Even when expanded polystyrene became available, it was only in sheets or beads. This is non-absorbent but still allows water vapour to get behind it and onto metal surfaces. Once there it would condense and collect and because the sheets would impede free airflow it would have more chance of increasing rather than evaporating. This is particularly the case in the bilge area as the bottom of the boat is nearly always cooler than the interior (I can't think of a time when it would ever be warmer, unless abandoned in winter) and so will always be a condensing surface!
    So, having no insulation will at least allow collecting water to drain to the lowest point where it can be pumped out, if it never dried out naturally.

    Why it should be:-
    Nowadays we have high performance, spray on, self-adhering insulation that forms a vapour barrier. The most common form is polyurethane foam, sprayed on with a two-part mixing system. It adheres well to almost any sound surface, forms a vapour-proof seal/barrier and has a much higher insulation value than even polystyrene sheets.
    The inside surface of the hull finished in such a material will always be a lot warmer than the hull itself and would rarely, if ever, form condensation on its surface.
    I spoke to a guy at the Crick boat show this year, selling such a system, and I asked him about the ventilation issue and he also agreed that the traditional trend seemed wrong with what is now available. Okay, he may be biased but he's been installing this for some time and I've not been able to find any gripes on forums yet.

    Does anyone else have a view, taking the above into account, as to why hulls are not insulated?
     
Loading...
Forum posts represent the experience, opinion, and view of individual users. Boat Design Net does not necessarily endorse nor share the view of each individual post.
When making potentially dangerous or financial decisions, always employ and consult appropriate professionals. Your circumstances or experience may be different.