Bulkheads

The friendliest place on the web for anyone who enjoys boating.
If you have answers, please help by responding to the unanswered posts.

DNT99611

Senior Member
Joined
Aug 7, 2015
Messages
186
Location
Kasilof, Alaska
The boats I am used to have dry exhaust and several water tight bulkheads. A good friend bought a 34 Californian last year and I was surprised there were no water tight bulkheads in it. With the posting of one going down due to wet exhaust failure

I am wondering if no water tight bulkheads is common on many of you folks boats?
 
Most recreational boats do not have watertight bulkheads.
 
The larger offshore cruising boats are more likely to have them. We have had 23 boats so far and never had them and have not ever sunk a boat so I really don’t see the need for them in coastal cruising. YMMV though.
 
WT bulkheads and WT doors don't work well with interior yacht design. No matter practical. Small boats, like 34', aren't really designed for offshore, regardless of how they're used. My boat has 5 WT bulkheads.
 
I built my 38 with four watertight compartments. Laz, ER, mid cabin, vee berth cabin. Between v-berth and mid cabin, there is a door that will leak unless screwed shut, which is easy to do if I am on board. All penetrations between compartments are in the overhead. So if a compartment filled, there could be some spill over.

Most likely compartment to fill is the ER. Boat should stay afloat with it completely flooded.

None of this was hard to do while designing and building. Always puzzled me why the practice is not more common.

I am part of a group that investigates marine incidents, including floodings and sinkings. On almost all of them the damage would have been far less if the flooding had been contained to a single compartment. Usually the ER.
 
My boat has no watertight compartments. The biggest challenge there are the hollow stringers. Even with the bulkheads sealed up, water can still flow through the stringers from the limber holes. However, the flow rate would still be somewhat restricted by the size of the limber holes in the stringers (and the small ones at the bottoms of the bulkheads).
 
While I understand the problems involved with interior design it seems like having the area most likely to have leaks, the engine room, water tight would be worth some trade offs. I have owned three boats as small as 32 foot that had three water tights. But they were work boats and not rec boats.
 
Custom boats can have whatever is desired.

Our 33ft 90/90 has a collision bulkhead and 2 WT doors ,one gets used to the raised threshold.

When having the doors made the mfg. wanted to use 1/4 aluminum instead of 3/16 with the claim the door would not dimple if holding a full head.

I stuck with 3/16 as the dimples would be a great talking point over a beer.


Read USCG Subchapter T to see what it takes to keep afloat.
 
A true watertight compartment has fittings outside the compartment to which compressed air (only about 3 PSI as I recall) is applied to check for leak-down over a specified period to ensure all wireways and other bulkhead penetrations are sealed. The idea is that if holed below the waterline, the closure of all watertight doors and hatches would allow the increasing air pressure in the compartment to eventually stop farther ingress of water. Not doable in 99.99% of privately owned vessels. Thus we citizens will be satisfied if the bulkhead is watertight up to say near the deck above without the requirement for sealing the high-up penetrations and watertight hatches.
 

Latest posts

Back
Top Bottom