leaking deck

kaniksu · #1 (**permalink**) 09-01-2006

I am looking at a 45 ft cutter, 1985 Liberty 458, that has three areas that show evidence of water leakage onto the house ceiling, probably due to the old and poor condition of the original teak deck. One leak is directly attributable to a deck prism. I am concerned about the integrity of the core laminate, Balsa I think. The boat is in Vancouver, BC so it has been in a very rainy climate for thelast 10 yrs. During a survey, what should be done to determine the extent of damage done and the over all integrity of the deck? Do invasive core samples have to be taken? If the deck is shown to have rotted areas is this a red flag to look for another boat or is this repairable?

camaraderie · #2 (**permalink**) 09-02-2006

kaniksu...
At that age and condition, needing to get rid of the teak deck is going to be a major expense and underlying repairs to the core are NOT fully forseeable until you have it all exposed. So hopefully all you have is a couple of trouble spots with local repairs to deal with. This can be a major job in terms of time and expense and mess if the core is rotted and you have to peel things back...but there is generally no structural reason why it should not be repairable.
If this is the 485 on yachtworld in Blaine Washington...it appears to be very well maintained from the pix. The good news is that you have removeable head liner and should be able to get right at the source of the leaks from underneath. If there is no delamination/rot at the source, then you can have some confidence that the problem is contained. If you do find rot, you really have no way of knowing how far it really extends even with some invasive coring so you need to take quite an "allowance" for repairs off the price of the boat. Hopefully, these are just minor repairs and not indicative of the condition of the rest of the deck.
On the deck prism, leaks are common (I have 7! ) and I "renew" my bedding every year or two as they start to drip. I would certainly remove this leaking prism as it will give you the opportunity to check the surrounding core, but I wouldn't view that particular leak as anything serious unless it has been allowed to continue for some time and the core is involved. Hope this helps!

sailandoar · #3 (**permalink**) 09-02-2006

Be scared, be very scared!

Localized damage is no big deal but with the teak deck it is hard to know where it is leaking, ?? everywhere ?? .. that assumes a fastened deck rather than a glued laminate which would be a wonderful thing if well done.

It should be pretty straight forward to determine the extent of the damage. Best to get an experianced and trustworthy surveyor if you think the boat is 'the one for you'. Otherwise RUN don't walk away from a potential deck rebuild. Could be like buying a hull and rig and getting to tear off the old deck and replace it. YUCK!!!. For someone who is looking for a project rather than a boat to sail it could be a good deal if it was cheap enough (nearly free) and boat was a very good one (Hinckley).

A medium soft rubber mallet (Walmart or Lowes) and a Wooden mallet ( soft wood.. make one from a piece of white pine. ) and start tapping. If you have any sort of ear at all you can HEAR the difference between a fairly solid deck and a hollow space filled with wet mush. Drill some holes (?3/16?)from the bottom side and check the tailings (dry solid or wet mush) and poke the core with a stiff piece of wire. Plug the hole with epoxy putty and piece of masking tape. If you do drill some holes onthe bottom of the deck, be sure to log the results on a map of the deck, and do a tap test on the top all around each drill site with rubber and wood mallet.

It's bad enough to have a glass deck over balsa ( like old pearsons ) but a fastened teak deck is 10,000 leaks waiting to happen.

sailingfool · #4 (**permalink**) 09-02-2006

Is it difficult to test a teak deck for water and delamination - doesn't the layer of dense wood hinder or prevent both sounding and moisture meter use? And no owner is going to let a prospective buyer start drilling holes into the deck. This is something I have no experience with, I just wonder how its done.

camaraderie · #5 (**permalink**) 09-03-2006

S-Fool...you are correct...you can't test it from the top. That's why I said I was glad the 485 has removeable headliner so you can easily get at the issue from inside the cabin. Owner may allow invasive testing if done from underneath and then covered up again...just to be able to prove a "clean" survey and know for himself what he is dealing with.

hellosailor · #6 (**permalink**) 09-03-2006

I would expect that a surveyor who had and knew how to use a moisture meter, could tell if the deck core was wet. Or for that matter, even by sounding it (tapping it) they should be able to get a really good idea.

But you will need to take that liner down, and may need to drill 1/4" holes to determine the extent of the damage. And if it does need repair...ka-ching, it can hurt to remove and rebed (or not) an entire teak decking job.

Definitely something to put on the sale contract as an escrow item unless you can be real certain about it not being a money pit beforehand. I like teak decks, but I'd be afraid of one that was leaking. If you can work with the owner, comfortably, by all means do. If you can't...be very very careful, this is a HUGE potential expense.

sailandoar · #7 (**permalink**) 09-03-2006

Opps! Major oversite on my part..... The teak overlay complicates the testing of the cored deck.

mmmm ???? ... ?

sailingdog · #8 (**permalink**) 09-04-2006

Unfortunately, since the boat has a teak deck, the moisture meter isn't going to be all that useful, and either is sounding (tapping) the deck. Teak decks already present a problem with moisture intrusion due to the number of holes caused by the screws that are used to fasten the teak deck to the underlying fiberglass deck. That is easily compounded by the leaks caused by the deck hardware. The water may also migrate along the underside of the teak and enter through the screwholes in many more areas of the deck than just the area by the leaking fixture.

hellosailor · #9 (**permalink**) 09-04-2006

"Unfortunately, since the boat has a teak deck, the moisture meter isn't going to be all that useful, and either is sounding (tapping) the deck. "
Why not? Both can be used against the UNDERSIDE of the deck to determine the state of the core.
Decks, like hulls, have two sides. Tapping and metering can be done from either side--with the same validity. The teak decking on the "far side" will have some effect, but not enough to swamp the indication of rotted or saturated core. Moisture meters are used (same type of meter, same purpose) on concrete slabs that are sitting on the ground in construction sites all the time. If the presence of 25,000 miles of dirt under the slab isn't going to affect a meter, an inch of teak won't stop it from working either. There are specific ranges for fiberglass, wood, concrete, etc. but the meters use the same principles, they're just calibrated differently and equipped with different probes to match the materials.

The trick is to find someone who knows how to use it--not just pressing the button and making impressive noises.

sailingdog · #10 (**permalink**) 09-04-2006

Quote:

Originally Posted by hellosailor

"Unfortunately, since the boat has a teak deck, the moisture meter isn't going to be all that useful, and either is sounding (tapping) the deck. "
Why not? Both can be used against the UNDERSIDE of the deck to determine the state of the core.
Decks, like hulls, have two sides. Tapping and metering can be done from either side--with the same validity. The teak decking on the "far side" will have some effect, but not enough to swamp the indication of rotted or saturated core. Moisture meters are used (same type of meter, same purpose) on concrete slabs that are sitting on the ground in construction sites all the time. If the presence of 25,000 miles of dirt under the slab isn't going to affect a meter, an inch of teak won't stop it from working either. There are specific ranges for fiberglass, wood, concrete, etc. but the meters use the same principles, they're just calibrated differently and equipped with different probes to match the materials.

The trick is to find someone who knows how to use it--not just pressing the button and making impressive noises.

A lot of boats have a ceiling that you would have to remove to get to the actual deck, which makes using a moisture meter much more difficult. Unless the boat in question has no deck lining or ceiling, then the use of a moisture meter is very unlikely to work well or accurately from the underside. When was the last time you saw a raw fiberglass ceiling inside 45' sailboat that wasn't under construction??? I doubt the owner will allow someone to remove or damage the ceiling just to do moisture meter readings for a survey.