Holes in the ceiling. Why?

[Boatyarddog]

Originally Posted by Bigjim

I've been tracking down leaks throughout the boat over the last couple of years. There were a some leaks coming from the cabin roof and I decided to pull down the vinyl headliner to track them down. The plan is to replace the headliner with wood paneling later.

Once the headliner was down I found two mysterious square holes on either side of the main hatch. The cabin roof has a hollow curved combing and these holes go through the fiberglass into these hollows. The square holes had wooden flanges with round holes cut into them but there was no vent and as far as I know there's no access to the outside world from this hollow.

There is nothing that I can see in the hollow that needs access but there are several screw holes allowing water to leak into the space. The screw holes are leaking since I removed the old hatch and have not sealed the hatch cover yet.

Does anyone know what these holes would be for? Photos attached:

Protective rail maybe? Like a boom kin, to keep your head safe from the boom, in case it falls when someone forgets to tension the boom lift while reefing?
That's my guess.
SV Cloud Duster

[Sailing4Jesus]

Originally Posted by drrossw

Not trying to be a smart ass but for general information, the ceiling on a sailboat is the covering over the frames. See the strip planking in the picture.

Well Shipmates I will add my Two Cents Worth. In The United States Navy there were NO CEILINGS. Ships and Small Boats have OVERHEADS, but Ceilings, Stairs, Floors, Walls, and such were the lingo of Sand-Crabs (Yard Birds), but never that of a Sailor. Not so much a Critical Issue, however, Tradition Should Be Kept Guarded, else comes the day when no one knows what in Sams Hill ya talking about mate.

Senior Chief

[cal40john]

Originally Posted by Sailing4Jesus

Well Shipmates I will add my Two Cents Worth. In The United States Navy there were NO CEILINGS. Ships and Small Boats have OVERHEADS, but Ceilings, Stairs, Floors, Walls, and such were the lingo of Sand-Crabs (Yard Birds), but never that of a Sailor. Not so much a Critical Issue, however, Tradition Should Be Kept Guarded, else comes the day when no one knows what in Sams Hill ya talking about mate.

Senior Chief

I guess you're a Sand-Crab when not talking about Destroyers and the like.

https://wavetrain.net/2011/09/24/fib...ll-structures/

The most basic sort of structural reinforcements are called floors and stringers. Floors are transverse sills in the bottom of a hull on which cabin soles are traditionally installed. Besides stiffening the bottom of the hull, floors provide critical support to the root of a sailboat’s keel where it meets the hull.

https://www.westsystem.com/wp-conten...and-Repair.pdf

Frames and floor timbers run athwartships at regular intervals along the keel. The symmetrical frames give the hull shape while the floors distribute the loads from the ballast keel or engine stringers out over even more of the planking.

[redneckrob]

As an aviator I used to always purposely say trigger words like "stairs" and "hat" to the boat people when we were embarked. Always tripped them offline, good for entertainment when you're really really bored.

[siamese]

Originally Posted by Sailing4Jesus

Purchasing any USED BOAT one must expect that he will be purchasing another man's problems. That is why one should hire a Certified Lloyds Marine Surveyor to perform a proper survey prior to purchasing ANY Boat, both Old or New, to be SURE of what you are buying. Any money spent for this Survey is money well spent.

Senior Chief, U.S. Navy, Retired

Preachy and wrong. Ouch.

[siamese]

Originally Posted by Sailing4Jesus

Well Shipmates I will add my Two Cents Worth. In The United States Navy there were NO CEILINGS. Ships and Small Boats have OVERHEADS, but Ceilings, Stairs, Floors, Walls, and such were the lingo of Sand-Crabs (Yard Birds), but never that of a Sailor. Not so much a Critical Issue, however, Tradition Should Be Kept Guarded, else comes the day when no one knows what in Sams Hill ya talking about mate.

Senior Chief

Still preachy, still wrong.

[Bigjim]

Originally Posted by Mike Banks

They look to me like provision was made for forced ventilation. I use extractive ventilation to suck the air out of the furthermost parts of the vessel using PVC small storm water conduits. One can use either sirocco type fans or axial displacement types in the conduits themselves. They are cheap, use little power, and are the MOST effective way to keep your vessel fresh and dry when you are absent for any length of time..

I also use it to draw air from under the bunks, the mattress sits on a lattice and is a close fit within the bunk sides, and the air is extracted from under each lattice and expelled out of the vessel. Computer cooling fans are tiny and work well--and run on low DC volts. There are few things worse than mouldy wet or damp bedding that never dries out because it never stops raining for long enough to dry a mattress.

The voids above the overhead do not connect to anything. I used an inspection camera and looked into both. They are empty and go nowhere. No ventilation.

I think they may have been an option for ventilation but was never installed.

The real problem is that there is nowhere for water to go if dorades were added.

[Benz]

Another two cents:
They look to me as though they were for a pair of support stanchions inside--something to grab onto when coming below. It's common on some older designs. The flat hollow on deck could have been for an exterior backing plate, or perhaps for adding a winch. Many boats have a winches just inside the dodger there.

[Benz]

Originally Posted by Sailing4Jesus

Well Shipmates I will add my Two Cents Worth. In The United States Navy there were NO CEILINGS. Ships and Small Boats have OVERHEADS, but Ceilings, Stairs, Floors, Walls, and such were the lingo of Sand-Crabs (Yard Birds), but never that of a Sailor. Not so much a Critical Issue, however, Tradition Should Be Kept Guarded, else comes the day when no one knows what in Sams Hill ya talking about mate.

Senior Chief

Sir, we hear very little of navy ships here or of their customs, except when they can't stop running into (colliding with?) other boats. Here we are concerned mostly with cruising sailboats, and in the business of their construction we use terms handed down by generations past of boatbuilders--some of which terms predate the USN. A "ceiling" is the interior lining of a hull, usually planks of wood as the picture showed. Under the decks and house is the "deckhead;" any transverse partition is a "bulkhead." A "floor" braces the frames of a boat above the keelson, but the surface provided for walking on is the "sole."
These terms precisely communicate essential ideas so that when boatbuilders converse they can understand one another. No doubt if we were to get into military shipbuilding we would have to learn a different set of words, but the ones we have now have served us in good stead for several hundred years.

[Bigjim]

I really doubt that these flat spots were intended for winches. They are too far from the cockpit to be useful or safe to use. You would only be able to use them while standing in the companionway or sitting on the cabin top.

There are no plywood backing plates or wood core in those locations. It doesn’t seem like the two holes were ever intended to be seen or used since there was a vinyl headliner installed with no access to these holes without removing or cutting the headliner.

The holes were also rough and not “finished” in any way. The other holes intended for dorades were cut with a hole saw. These were rough sawed and not even perfectly symmetrical. Since there is a void in that section of the cabin top these holes may have simply been intended as passive ventilation for these spaces so that water doesn’t get trapped in there.