Going nuts - can't figure out the source of a leak

This might be an unsolvable question, but figured I would try you guys here just in case your collective genius can find something that I'm missing.

The problem: The floorboards underneath one of the heads in my 1986 Nova Sundeck continuously seem to be getting wet. Not a lot, but definitely damp. This is either caused by, or is the cause of, water damage to the veneer along a couple of walls directly outside of the head. I've attached pictures of the floorboards under the head [picture 1], and the water damage to the walls [picture 2].

Complicating things is that our water heater exploded about a year ago, flooding this area and probably causing some of the damage to the walls that you can see in Picture 2. I was gone at the time though and my girlfriend swears that the damage that is there now is unrelated to the water heater (she's usually right about such things).

My initial thought was that one of the pipes leading into or out of the head was leaking and causing the water damage, which seemed to be logical given that there was a bit of wetness coming out of the raw water inlet line when we flushed the electric motor. I removed the head completely and blocked off that pipe while I dried out the floors. At this point I noticed that we also had other issues, including a macerator which had broken in half and a leaking vented loop coming from the bilge pump underneath the holding tank. This meant that the holding tank wasn't holding anything, and all waste products (we use our heads for #1 only) were being pumped directly out by the bilge pump with some leaking out through the leaky vented loop which was underneath the sink in the head. I figured this too could have been a source of the wetness and water damage.

The head has been off for almost a week now and the vented loop and holding tank were all fixed, and everything was dried thoroughly. However, the moisture still seems to be coming back. (note: walls do seem to have stayed dry, although its hard to tell for sure).

So here are my guesses:
1. The pipes for the raw water inlet could be 'sweating', causing the moisture that is still coming back there. They're old hoses, so I guess this could be possible. You can see in picture three, it is the hose on the right hand side of the picture leading into the vented loop. Possibly supporting this theory is that the two small holes where the raw water line comes in appear to be damp, whereas the other holes (the one above and the one to the bilge) do not.

2. There is water somehow making its way to this cavity either from a leaky window, or from some other area that I can't find. There is a window nearby that has leaked in the past [see picture 4], but the water would have to travel along the inside of the hull behind the walls and pool underneath the head. I haven't found evidence for this in any other area, but its hard to get any visibility back there.

3. I'm crazy and there is no moisture, or the moisture that is there on the floor boards is just residual or caused by humidity or evaporation from the bilge, and all previous water damage to the veneer was caused by the slowly leaking raw water line when it was hooked up, as well as the previous damage from the water heater.

Sorry if this was too long of a narrative, but clearer perspectives would be very much appreciated. I've been staring at this issue for too long and now its starting to seem like the boat is conspiring against me.

Note: Picture 2 is upside down. Not sure how that happened.

Greetings,
Mr. c. It's the elephant...

I'm assuming the wall is a veneer, over particle board? If so the wall may take quite a while to completely dry. I would start with a dehumidifier and dry the space for a few weeks. If the moisture level doesn't improve within a week, time to start looking for another leak source.

Regarding sweating pipes. A sweating pipe is caused by cold fluids going through the pipe and warm humid air condensing on the pipe. An army would have to be using the bathroom to generate enough constant flow to generate any significant condensation.

From the upside down picture, it appears that your moisture is coming from the bottom up. That's what makes me think the inside of the walls are still wet.

Please bear in mind that this information is probably only worth what you paid for it. Hope some of it helps.

Ted

Is your shower and cooking well vented? Moisture shows up in cool places, Every shower, every pot of boiling water, your breath, all needs to be replaced with drier air. Having a port open isn't going to get rid of all the moisture. If you can't find a leak, it's probably you. If you slept in a car in cold weather, the windows would be covered in moisture in a few hours. In warm weather the moisture is still there, but the warmer air holds it until it rubs against something cool.

More than likely the wood floor has soaked up a lot of water and it's going to take some time for it to dry out.

I doubt your walls are made of particle board or they would have started to blown out by now. Either way once the veneer gets that wet there is not much you can do about the discoloration of the veneer.

Put a dehumidifier in the room for several days and see what happens.

Is that vented loop in the picture below the water line?

A roll of masking tape and a roll of paper towels may help determine the source.

Water leaks can be a PITA to track down..

It's not always windows, any place you have attachments fastened with screws that penetrate the deck, gunnel or superstructure are suspect. if you have rail stanchions above the leak area, back the screws out and reseal them.

Do you have teak decks? Nova Sundeck is Taiwanese? Has it rained there recently? Is there a window above?

Look for soft decks and sidewalls, any other source of leaks including mentioned by Edelweiss.

Your wiring is a mess and do I see Marettes?

Xsbank said:

Your wiring is a mess and do I see Marettes?

Click to expand...

It looks like it. But it's hard to tell in that picture.

Thanks for all the comments. My current leading theory is similar to yours @Lepke- there is a fairly large opening in this compartment that leads down to the bilge. My thought is that maybe the water in the bilge is evaporating during the warm part of the day, getting trapped in this area, and then condensing back down once it cools off at night.

@Xsbank and @Edelweiss: no teak decks, and the hull is all fiberglass. There is a window above, but it hasn't rained lately or been that humid. Still could be the source, I suppose. The area is impossible to get to since there is a cabinet in the way that is fully sealed up. I'm going to wash the boat down tomorrow though and see if it makes matters worse.

Re: the wiring situation, agreed its not great, and yes those are twist-on wire connectors. Remnants of the previous owner. We're liveaboards and don't take the boat out much (ever, really) so it hasn't been an issue. We're also both students so our wallets don't have the flexibility to take on any really big projects right now, which has me very bummed about the damage to the veneer.