Waterline on canalboat how to determine holes for water waste ?

[Peter009]

Firstly please forgive my lack of knowledge in this area which is why I am posting this question so I do not get this wrong. as this is far too important to make a mistake  We are currently at the stage of where the plumbing is near completion and about to look at wastes for the water (sink, bath, washing machine - not toilet waste) as our boat has never been launched yet we are unclear as to where the waterline may be and looking logically at it would I be right in that where the engine exhausts are already at the top of the hull we would be safe to create the wastes there which is just under the rub line at the top of the hull.  I expect this will be higher than needed but without actually determining how she floats when launched we either finish the plumbing now being over high for the waste or have to leave it until launched which will impact other work we need to do on the boat.

 

Does anyone have any suggestions here any pictures with examples of water waste outlets would also be appreciated.

 

Again I have a lack of knowledge in this area however am learning as I go alone and recognise the importance of not getting this wrong or we wont potentially have a boat at all 

 

Thanks

[Alan de Enfield]

14 minutes ago, Peter009 said:

.........….please forgive my lack of knowledge in this area which is why I am posting this question

This doesn't answer your question of how to determine your 'water line' but just a reminder that for a 'private' boat any hull openings SHOULD be 10" above the water line. For any commercial / hire / rental / passenger / 'shop' type boats then it is MANDATORY  for any hull openings to be at least 10" above the water line.

 

This can be very difficult to achieve on the sinks / basins on some canal boats because the drain (plug-hole) in the sink may not even be 10" above the water line, in which case you need to put the actual hull fitting as high as possible in the hull, whilst leaving enough 'run-off' to empty the sink. You can achieve the 10" by having a 'swan neck' in the pipe to help minimise any in-flow of water.

 

Your bath will have its outlet well below the water line and you will need to install a  pump in line to lift the water up to the hull-fitting.

Your washing machine has its own pump but these are designed to lift the water about 500mm from the base of the machine and this may not be sufficient in your boat and, again, you will need to install a pump.

 

From the BSS

 

The provisions of this section of Part 10 in the 2002 BSS Standards are mandatory for non-private boats where applicable.

To reduce the risk of your boat sinking if it keels over or is excessively weighed down, it's a good idea for privately owned boats to only have openings which are at a height of at least 250mm (10ins) above the waterline. Where openings are necessary below this level this risk can be reduced by ensuring that these openings are permanently and securely connected to ducts or pipes, which are watertight up to that level.

Self-draining cockpits may not be able to meet the 250mm (10ins) recommendation but, for privately owned boats, it's a good idea to stop water getting into other parts of the hull by incorporating non-return valves in the drains and/or having bulkheads or cills up to a height of 150mm (6ins).

A weed hatch, if not properly secured, can allow water into the bilges of a boat, which could ultimately cause it to sink. It's advisable for privately owned boats to have a secure and watertight weed hatch which reaches to at least 150mm (6ins) above the waterline, when the boat is loaded up as normal. [10.3]

 

 

 

Edited March 10, 2019 by Alan de Enfield

[Murflynn]

my understanding of the precautions to be taken against 'downflooding' according to the BS/EN/ISO Standards is that the opening should be at least 250mm above the waterline, which may vary if the boat is heeled over for some reason.  However for a canal boat this seems a little extreme. 

Certainly setting the openings at the same level as the exhaust will be adequately safe, especially bearing in mind that most boats trim by the stern (i.e. the stern is lower in the water than the bow), and the exhaust is near the stern.

Just as an aside, the downflooding regulations allow a much lower outlet provided there is an isolation valve fitted inside the boat, and the pipework between the valve and the skin fitting is adequately robust so that it cannot be dislodged and leak.

of course, only you will know (one day, maybe not today) where the waterline will be when the boat is launched.

[Boater Sam]

The BSS specifies the minimum height above water line, for hire boats I believe its 250mm, hard to do with galley sink wastes without pumping them. But if the internal waste pipes cannot come apart, then it can be lower providing that internally it is sealed to this height.

Shower will obviously have to be pumped, a Whale is best. Wash basin you may do same as sink, solvent welded pipe work is easiest onto threaded hull fittings.

 

Which hull builder? Can you find the same hull already in the water and look at that? A lot depends on how deep you want to ballast the front of the hull, the uxter plate is normally 20mm or so under water with full water and fuel tanks.

[Sea Dog]

32 minutes ago, Peter009 said:

Again I have a lack of knowledge in this area however am learning as I go alone and recognise the importance of not getting this wrong or we wont potentially have a boat at all 

Are you not working to a set of rules, at least as guidance? Alan has quoted the BSS above, but there's also the RCR (Recreational Craft Regulations).  Iirc,   you don't have to comply with the RCR  for your own personal boat if you're not selling it within 5 years, but it may be a useful guide. Someone who knows this better may be along shortly. 

Edited March 10, 2019 by Sea Dog
Miss-credit!

[Alan de Enfield]

4 minutes ago, Sea Dog said:

Tony has quoted the BSS above,

?????

[Sea Dog]

Just now, Alan de Enfield said:

?????

Yeah, that's what I said... Alan.  I just made a small spelling error. 

 

[Tony Brooks]

Personally I doubt the OP will find it easy to establish the eventual waterline on a boat that is on dry land - I read his post as implying the boat is not yet afloat.

 

If he wants to try then:

 

 

A:  Weight of hull + Weight of ballast + Weight of fit out and equipment/stores. That tells him how much water will be displaced

 

B:  Then 1/2 length of front swim X beam + 1/2 length of stern swim X beam + length of centre section X beam. That gives the area of the base plate very roughly.

 

Then A divides by B will give the average depth of submersion so measure that length up from the base plate but the actual waterline will differ as tansk fill and empty and extra ballast is added to trim the boat.

 

If not building to the RCD then I would just fit them as high as reasonably practical on my own boat. As Sam says the true height is to the top of the sink/basin whatever as long a sthe internal pipework is well secured and strong.

[Sea Dog]

6 minutes ago, Tony Brooks said:

Personally I doubt the OP will find it easy to establish the eventual waterline on a boat that is on dry land 

True, but wouldn't an inch above the counter would be a good starting point?

[Tony Brooks]

24 minutes ago, Sea Dog said:

True, but wouldn't an inch above the counter would be a good starting point?

I agree, its as good as any other method.

[Boater Sam]

56 minutes ago, Sea Dog said:

True, but wouldn't an inch above the counter would be a good starting point?

Said that only uxter plate, same thing? Oh, and I went metric!

I like a nearly horizontal gunwalel with the boat fully loaded but I see all these modern boats that look unballasted with the bow pointing at the stars, god knows why, they must be a pig in a cross wind.

[Sea Dog]

12 minutes ago, Boater Sam said:

Said that only uxter plate, same thing? Oh, and I went metric!

Sorry Sam, so you did - and, oddly enough, I would usually have said uxter too. Still, we have concensus... and only I said an inch in case @mrsmelly was reading! 

 

[mrsmelly]

10 minutes ago, Sea Dog said:

Sorry Sam, so you did - and, oddly enough, I would usually have said uxter too. Still, we have concensus... and only I said an inch in case @mrsmelly was reading! 

 

 Bloomin right too!! We have no need of Johny Foreigner measurements innitt!! I never ever had a Stein of beer at Oktoberfest ?

[Peter009]

2 hours ago, Sea Dog said:

Are you not working to a set of rules, at least as guidance? Alan has quoted the BSS above, but there's also the RCR (Recreational Craft Regulations).  Iirc,   you don't have to comply with the RCR  for your own personal boat if you're not selling it within 5 years, but it may be a useful guide. Someone who knows this better may be along shortly. 

Yes we are aware of the rules but rules apart we want to be higher than what is recommended as the boat has never been on water so it is very difficult to determine the exact waterline at this stage we may or may not need to put more ballast in or take some out when it comes to it but what we are trying to ensure is that we are well above the water line regardless it it is a bit low in the water we will be safe where we are planning these openings.  I am really double checking with people on their views on this 

2 hours ago, Boater Sam said:

The BSS specifies the minimum height above water line, for hire boats I believe its 250mm, hard to do with galley sink wastes without pumping them. But if the internal waste pipes cannot come apart, then it can be lower providing that internally it is sealed to this height.

Shower will obviously have to be pumped, a Whale is best. Wash basin you may do same as sink, solvent welded pipe work is easiest onto threaded hull fittings.

 

Which hull builder? Can you find the same hull already in the water and look at that? A lot depends on how deep you want to ballast the front of the hull, the uxter plate is normally 20mm or so under water with full water and fuel tanks.

I have tried to find the same boats but very difficult we have a cuttwater who no longer make them and even if we were to go from those pics we are still not sure with all of our interntal kitchen bathroom etc that it will float the same so we are being over the top careful if we want to carry on or we will have to wait to get the water installed etc

[Peter009]

3 hours ago, Alan de Enfield said:

This doesn't answer your question of how to determine your 'water line' but just a reminder that for a 'private' boat any hull openings SHOULD be 10" above the water line. For any commercial / hire / rental / passenger / 'shop' type boats then it is MANDATORY  for any hull openings to be at least 10" above the water line.

 

This can be very difficult to achieve on the sinks / basins on some canal boats because the drain (plug-hole) in the sink may not even be 10" above the water line, in which case you need to put the actual hull fitting as high as possible in the hull, whilst leaving enough 'run-off' to empty the sink. You can achieve the 10" by having a 'swan neck' in the pipe to help minimise any in-flow of water.

 

Your bath will have its outlet well below the water line and you will need to install a  pump in line to lift the water up to the hull-fitting.

Your washing machine has its own pump but these are designed to lift the water about 500mm from the base of the machine and this may not be sufficient in your boat and, again, you will need to install a pump.

 

From the BSS

 

The provisions of this section of Part 10 in the 2002 BSS Standards are mandatory for non-private boats where applicable.

To reduce the risk of your boat sinking if it keels over or is excessively weighed down, it's a good idea for privately owned boats to only have openings which are at a height of at least 250mm (10ins) above the waterline. Where openings are necessary below this level this risk can be reduced by ensuring that these openings are permanently and securely connected to ducts or pipes, which are watertight up to that level.

Self-draining cockpits may not be able to meet the 250mm (10ins) recommendation but, for privately owned boats, it's a good idea to stop water getting into other parts of the hull by incorporating non-return valves in the drains and/or having bulkheads or cills up to a height of 150mm (6ins).

A weed hatch, if not properly secured, can allow water into the bilges of a boat, which could ultimately cause it to sink. It's advisable for privately owned boats to have a secure and watertight weed hatch which reaches to at least 150mm (6ins) above the waterline, when the boat is loaded up as normal. [10.3]

 

 

 

Hi Alan, thanks for the image.  I have worked out that the outlets will be above the weed hatch and pretty much above mostly everything  attached is a picture of where the exhausts for the engine are and the top of the engine bay channel gutter outlet and I am thinking of following that line where they are around to the kitchen and bathroom 

[Alan de Enfield]

10 minutes ago, Peter009 said:

I have worked out that the outlets will be above the weed hatch

I think that's about all you can do in the absence of any 'help' from the manufacturer.

 

Are you building to RCD ?

If so maybe your surveyor could suggest likely water line levels (or are you self-certifying ?)

[Peter009]

The surveyor did say I was going to be higher than needed but again nobody really knows until she is launched but I guess if the engine exhausts go under water then there has to be a bigger issue overall so apart from going a few inches higher to a hatch opening that is about the highest I can go realistically.  Is there any plumbing fittings for the waste that close when not in use out of interest, i.e some sort of sensor that works out that water is going through it internally other than that they remain closed ?  am thinking also about insects etc and maybe random fish jumping in   

[Alan de Enfield]

12 minutes ago, Peter009 said:

The surveyor did say I was going to be higher than needed but again nobody really knows until she is launched but I guess if the engine exhausts go under water then there has to be a bigger issue overall so apart from going a few inches higher to a hatch opening that is about the highest I can go realistically.  Is there any plumbing fittings for the waste that close when not in use out of interest, i.e some sort of sensor that works out that water is going through it internally other than that they remain closed ?  am thinking also about insects etc and maybe random fish jumping in   

Non-Return valves (mentioned in the cut & paste BSS extract)

Manually operated Sea-Cocks.

 

Going 'high' will probably mean that you will need an additional pump-out pump on your washing machine waste pipe. You can power it from the machines own pump so it only activates when needed.

Edited March 10, 2019 by Alan de Enfield

[Peter009]

On 10/03/2019 at 12:13, Alan de Enfield said:

Non-Return valves (mentioned in the cut & paste BSS extract)

Manually operated Sea-Cocks.

 

Going 'high' will probably mean that you will need an additional pump-out pump on your washing machine waste pipe. You can power it from the machines own pump so it only activates when needed.

Thanks Alan

[Sea Dog]

On 10/03/2019 at 12:02, Peter009 said:

The surveyor did say I was going to be higher than needed but again nobody really knows until she is launched....

She's not going to be hugely different in draught (hence waterline) from other boats using the same hull from the same builder though. Can't you find one of those and make a judgement by the position from the top rubbing strake (or similar common fixed feature)?

[Peter009]

4 minutes ago, Sea Dog said:

She's not going to be hugely different in draught (hence waterline) from other boats using the same hull from the same builder though. Can't you find one of those and make a judgement by the position from the top rubbing strake (or similar common fixed feature)?

Hi have done and I think we are safe where we are planning I think there will be a bigger issue if she goes too low in any case.  She has had a full survey and the hull is perfect and we dont have a huge amount of weight in fittings on the boat so as long as we position the water tank centre at the bow end am confident we are on the right track now, 

[Sea Dog]

2 minutes ago, Peter009 said:

Hi have done and I think we are safe where we are planning I think there will be a bigger issue if she goes too low in any case.  She has had a full survey and the hull is perfect and we dont have a huge amount of weight in fittings on the boat so as long as we position the water tank centre at the bow end am confident we are on the right track now, 

Good to hear Peter - exciting times!

 

[Murflynn]

4 minutes ago, Peter009 said:

.............. I think we are safe where we are planning I think there will be a bigger issue if she goes too low in any case. 

??  meaning what exactly  ??

[Peter009]

On 13/03/2019 at 08:18, Murflynn said:

??  meaning what exactly  ??

.............. I think we are safe where we are planning I think there will be a bigger issue if she goes too low in any case - not really that hard to work it out is it