Water seeping through hull

[Fourfours]

Hello I would appreciate some advice. I had water in my narrowboat cabin bilge that was sitting there for a number of months. I thought I found the source of the leak (calorifier). There was significant rust and am in the process of drying, grinding and fertaning. One area along the cabin sides would not dry and on closer inspection there seems to be water seeping in very slowly though a tiny hole. I called the person who sold me the boat who reckons that it’s water that got trapped between the plates (it’s been over plated). Does this sound like a reasonable explanation? If there was water coming in through the outer plate would it be coming in really fast due to the pressure? 

 

Also so what’s the best solution. Do I just need to wait till it stops seeping and hope that it’s dry enough?

 

any thoughts or advice would be much appreciated 

[Alan de Enfield]

22 minutes ago, Fourfours said:

any thoughts or advice would be much appreciated 

It is not 'normal'. Water should stay on the outside of the boat.

 

It could be trapped water between the overplating but if it is the overplating was probably not done properly.

 

I would suggest that you quickly get it lifted out and surveyed (did you have a survey when you bought it ?)

 

It will only get worse and maybe a slight 'knock' and it would become a big-hole and the boat will be soon resting on the bottom.

[Guest]

25 minutes ago, Fourfours said:

Hello I would appreciate some advice. I had water in my narrowboat cabin bilge that was sitting there for a number of months. I thought I found the source of the leak (calorifier). There was significant rust and am in the process of drying, grinding and fertaning. One area along the cabin sides would not dry and on closer inspection there seems to be water seeping in very slowly though a tiny hole. I called the person who sold me the boat who reckons that it’s water that got trapped between the plates (it’s been over plated). Does this sound like a reasonable explanation? If there was water coming in through the outer plate would it be coming in really fast due to the pressure? 

 

Also so what’s the best solution. Do I just need to wait till it stops seeping and hope that it’s dry enough?

 

any thoughts or advice would be much appreciated 

Judging by people who I know with overplated boats, I would say that this is a possibility.

[hider]

If it is properly overplated, no water should get between the original hull and the overplate from the outside.

But if the bilge has been flooded then it could well get in from the inside but the original hull would have to be in an exceptionally poor condition. In which case prior to overplating it would have sunk.

The seller may be correct, or he may be very optimistic. 

[Murflynn]

a little knowledge of psychology tells me that the seller will always be very optimistic.

[Fourfours]

19 minutes ago, hider said:

 

If it is properly overplated, no water should get between the original hull and the overplate from the outside.

But if the bilge has been flooded then it could well get in from the inside but the original hull would have to be in an exceptionally poor condition. In which case prior to overplating it would have sunk.

The seller may be correct, or he may be very optimistic. 

 

Thanks for your replies. I’m interested in what the chance is that it could be canal water? The survey was ok and done last year. There were no parts tested below 4mm but I understand that they don’t test the entire hull. The internal rust is not terrible. I’d say a mm in most places and a 2-3 mm in a few spots. The water is coming in really slowly, as in over night it will dampen the surrounding area but there won’t be a puddle. Are there any other possible explanations? 

 

Thanks again

[WotEver]

2 minutes ago, Fourfours said:

Are there any other possible explanations? 

A porous well on the overplate?

[MtB]

1 minute ago, Fourfours said:

The water is coming in really slowly, as in over night it will dampen the surrounding area but there won’t be a puddle. Are there any other possible explanations? 

 

I'd say the only possible explanation is the overplating is not watertight, leading to the gap between the plating and the old hull filling with water. 

 

Overplating is a really REALLY BAD idea in my opinion, because neither you, your surveyor nor the bloke doing it has any way of testing the new overplating for watertightness. 

 

 

[bizzard]

you could try pouring some fine ash dust from your stove over the side roughly adjacent to where you think the hole is on the inside to see if it stops the leak, although if its very slow there might not be enough suction force at the hole to suck it in and block it.

[TheBiscuits]

I'm with @hider on this one. It is quite possible that water seeped through the original hull behind the plating from the inside.

 

If it's that slow a weep, and your bilge was flooded for a while wait for a few weeks and keep checking.

 

If the water gets worse worry, if it gets even slower don't worry at all.

[Fourfours]

8 minutes ago, Mike the Boilerman said:

 

I'd say the only possible explanation is the overplating is not watertight, leading to the gap between the plating and the old hull filling with water. 

 

Overplating is a really REALLY BAD idea in my opinion, because neither you, your surveyor nor the bloke doing it has any way of testing the new overplating for watertightness. 

 

 

 

1 minute ago, TheBiscuits said:

I'm with @hider on this one. It is quite possible that water seeped through the original hull behind the plating from the inside.

 

If it's that slow a weep, and your bilge was flooded for a while wait for a few weeks and keep checking.

 

If the water gets worse worry, if it gets even slower don't worry at all.

So if it get’s better then the water must have come from the inside?

 

otherwise would the advice be to get the boat out the water to check the over-plating? The boat is old (1980) and has been extensively over-plated. I understand that it’s not a good idea but the work was completed before I bought it. If I could go back in time I would be more thoughtful about whether to purchase an extensively over plated boat but hindsight is... well hindsight!

40 minutes ago, hider said:

If it is properly overplated, no water should get between the original hull and the overplate from the outside.

But if the bilge has been flooded then it could well get in from the inside but the original hull would have to be in an exceptionally poor condition. In which case prior to overplating it would have sunk.

The seller may be correct, or he may be very optimistic. 

My understanding is that it spent many years on dry standing so if there was water in the hull could it not have corroded during this time?

[Capella247]

Maybe speak to your surveyor and ask for their advice.   In my experience over the years the ones I’ve commissioned to do a survey have been happy to refer to their notes discuss the survey and the boat at a later date.  

[Fourfours]

2 minutes ago, Capella247 said:

Maybe speak to your surveyor and ask for their advice.   In my experience over the years the ones I’ve commissioned to do a survey have been happy to refer to their notes discuss the survey and the boat at a later date.  

Thanks good advice 

[TheBiscuits]

Do you have any photos of the overplating, and do you know who did it?

[blackrose]

44 minutes ago, Fourfours said:

Thanks for your replies. I’m interested in what the chance is that it could be canal water? The survey was ok and done last year. There were no parts tested below 4mm but I understand that they don’t test the entire hull. The internal rust is not terrible. I’d say a mm in most places and a 2-3 mm in a few spots. The water is coming in really slowly, as in over night it will dampen the surrounding area but there won’t be a puddle. Are there any other possible explanations? 

 

Thanks again

 

So just to clarify, where is the hole you spoke about on your first post? What sort of insulation do you have and presumably you have taken the wooden lining off and scraped away the sprayfoam (or taken away the polystyrene or rockwool) so that you can see the dampness on the steel? 

 

Can you actually see the hole and see the water coming in?

[Keeping Up]

As the owner of a boat that had to be overplated, I would disagree that overplating is a bad thing. If it is done badly it is a bad thing, if it is done well it is a good thing.

[Fourfours]

4 minutes ago, blackrose said:

 

So just to clarify, where is the hole you spoke about on your first post? What sort of insulation do you have and presumably you have taken the wooden lining off and scraped away the sprayfoam (or taken away the polystyrene or rockwool) so that you can see the dampness on the steel? 

 

Can you actually see the hole and see the water coming in?

If you sponge it then remove the sponge water very slowly reappears. Everything has been scraped away from the hull so you just get damp metal

[Fourfours]

17 minutes ago, blackrose said:

 

So just to clarify, where is the hole you spoke about on your first post? What sort of insulation do you have and presumably you have taken the wooden lining off and scraped away the sprayfoam (or taken away the polystyrene or rockwool) so that you can see the dampness on the steel? 

 

Can you actually see the hole and see the water coming in?

 

[blackrose]

So you think the hole is in the baseplate. Is it the baseplate that's been overplated and can you actually see the hole?

 

If not, then how do you know that the water isn't slowly running in from another area on the floor and coming in through a scupper from behind the wall lining?

 

Edit: if it is water between plates on the outside of the baseplate then why would it flow upwards?

Edited July 3, 2019 by blackrose

[Karen Lea Rainey]

I would suggest that because  you have taken ballast out from this floor area that you have re balanced the boat, the steel cross members going across your boat do not go to the very edge, ie water from under the floor will continue to seep around those stretchers for a good few days yet. Put a few nappies down to soak the dampness up and you may be able to see more clearly where the water is coming from. It could have been internal water from your plumbing as well,  which you need to eliminate. (A previous or continuous pipe leak).

If you find a leak use some modelling putty  like 'milliput' which can be purchased from places like Hobby craft and aquatic shops to get you out of trouble until you identify the real cause of the water and spend serious money getting your boat out of the water or further welding that may or may not need doing.

[blackrose]

27 minutes ago, Karen Lea Rainey said:

I would suggest that because  you have taken ballast out from this floor area that you have re balanced the boat, the steel cross members going across your boat do not go to the very edge, ie water from under the floor will continue to seep around those stretchers for a good few days yet. Put a few nappies down to soak the dampness up and you may be able to see more clearly where the water is coming from. It could have been internal water from your plumbing as well,  which you need to eliminate. (A previous or continuous pipe leak).

 

 

Exactly, everyone's read the OP's description, run with it and been jumping to conclusions which may or may not be the case.

 

Question what you're being told and think laterally people.

Edited July 3, 2019 by blackrose

[Fourfours]

38 minutes ago, blackrose said:

So you think the hole is in the baseplate. Is it the baseplate that's been overplated and can you actually see the hole?

 

If not, then how do you know that the water isn't slowly running in from another area on the floor and coming in through a scupper from behind the wall lining?

 

Edit: if it is water between plates on the outside of the baseplate then why would it flow upwards?

I can’t see a hole but it is quite rusty. The photo is where the baseplate meets the cabin side. It’s sort of oozing water. There’s a nappy there currently to soak it up. I’m not sure what a scupper is, excuse my ignorance. There was some old ballast that was polystyrene with poured concrete on top. That’s been removed but the water seems to be coming from the seam.

[Fourfours]

37 minutes ago, Karen Lea Rainey said:

I would suggest that because  you have taken ballast out from this floor area that you have re balanced the boat, the steel cross members going across your boat do not go to the very edge, ie water from under the floor will continue to seep around those stretchers for a good few days yet. Put a few nappies down to soak the dampness up and you may be able to see more clearly where the water is coming from. It could have been internal water from your plumbing as well,  which you need to eliminate. (A previous or continuous pipe leak).

If you find a leak use some modelling putty  like 'milliput' which can be purchased from places like Hobby craft and aquatic shops to get you out of trouble until you identify the real cause of the water and spend serious money getting your boat out of the water or further welding that may or may not need doing.

The only leak I have been able to identify is from the metal piping leading to the immersion tank. I think this was the source of most of the puddles at the stern but I also think the dampness spread through the polystyrene so more areas were damp without there being water. It’s been drying out for a while and all the other areas are dry but this spot, which is on the opposite side to the immersion tank. I do think that my windows could be leaking though. The water does appear as if it’s coming up from the baseplate but again it’s sort of hard to tell because it so slow. 

Thanks for all your responses! I guess it’s hard to diagnose a problem from poor descriptions and blurry photos. 

[Karen Lea Rainey]

With the current hot weather I would have thought that any patch of water would be dry within a couple of days, keep an eye on it, dont do any more chiseling or scraping and get some "Milliput"it can be pushed into small leaky areas and make a semi, temporary repair which should last until your boat is due to come out of the water. It will work even in slightly damp areas. 

[Fourfours]

14 minutes ago, Karen Lea Rainey said:

With the current hot weather I would have thought that any patch of water would be dry within a couple of days, keep an eye on it, dont do any more chiseling or scraping and get some "Milliput"it can be pushed into small leaky areas and make a semi, temporary repair which should last until your boat is due to come out of the water. It will work even in slightly damp areas. 

Thanks again, that’s helpful advice... Milliput it is then!