As a followup to a previous question: There are many examples of folks adding storage by removing foam from under the forward Vberths. How will this affect flotation if the boat is swamped? I too would like to build storage compartments in this area, but not at the expense of having the boat sink like a rock when swamped. Any comments are welcomed.
You are using an out of date browser. It may not display this or other websites correctly.
You should upgrade or use an alternative browser.
You should upgrade or use an alternative browser.
CD 22 flotation question
- Thread starter anchorout
- Start date
My 2008 CD22 came with hatches under the berth and no foam. A 22' boat is not required by US law to remain afloat if swamped.
Based on the fact that newer boats have hatches and no foam and that older boats which did have foam had a fairly haphazard installation of foam in the forward compartments, I would guess that the inclusion of foam under the berth was not a real design issue. It was probably something like "there is a void and I have a foam gun, so what the heck...", rather than some design calculation that said "if we put x cubic feet of foam under the berth the boat can remain afloat for this long."
If the designers had required this area to be full of foam, the installation would be better and the factory would be telling people not to do this every time it came up.
I would expect that even if the CD22 had the under berth area full of foam and flooded in moderate seas, at best the boat would float upside down with just the hull entry line (curvy pointy edge of the hull near where the trailer strap attaches) out of the water. You'd have something to hang on to, but that's about it.
Based on the fact that newer boats have hatches and no foam and that older boats which did have foam had a fairly haphazard installation of foam in the forward compartments, I would guess that the inclusion of foam under the berth was not a real design issue. It was probably something like "there is a void and I have a foam gun, so what the heck...", rather than some design calculation that said "if we put x cubic feet of foam under the berth the boat can remain afloat for this long."
If the designers had required this area to be full of foam, the installation would be better and the factory would be telling people not to do this every time it came up.
I would expect that even if the CD22 had the under berth area full of foam and flooded in moderate seas, at best the boat would float upside down with just the hull entry line (curvy pointy edge of the hull near where the trailer strap attaches) out of the water. You'd have something to hang on to, but that's about it.
If I was really worried about floatation, I would have air bags to inflate in the forward cabin. But in reality the chance of sinking a C Dory is very slim. I usually carry an inflatable boat, and that is my "life raft"--if that should happen. I have never taken the foam out--but agree with ssobol's assessment. The reason for not taking the foam out is that I am lazy--and don't really need that storage space, but it would be nice to have...
I tend to agree with ssobol [Edit: I also agree with Thataway, but his post wasn't there when I started typing my reply]. I've paid close attention to all the threads (many posts) about people delving into the v-berth on their 22's to remove foam. Saying that the installation is "random" is putting it mildly. So for starters you may or may not have foam and/or any given quality under there to begin with.
It is possible to do calculations to find out just how much foam (or really "flotation" of some sort or another, it can be any form of trapped air, etc.) would be necessary to float the boat. Another step would be to figure out where to put the foam so as to have the boat float as near to level as possible (presuming that is desirable, but perhaps it does not matter). A seat of the pants guess tells me that the foam that may sometimes have been installed by C-Dory builders in the past at certain times did not take those calculations into account. It has also always been open-celled, from what I can tell, which means it's subject to soaking up water over time and thus becoming ineffective (I would use closed cell foam or some sort of air bladder(s) myself).
I realize that nothing I'm saying above IS a calculation (although there are calculations that can be performed), and I don't think anyone should do something they are not comfortable with on my advice. Basically, I have read a small amount on the subject (because there are folks who have calculated the amount and placement of flotation for their sailboats and I have read those articles).
If I did want positive flotation in my 22, I would be calculating it and then adding closed cell foam in the recommended amount and location. I suspect it would be spread throughout the boat (and thus taking up valuable-to-me stowage and cockpit lounging space). I'm fine with it the way it is (and plan to remove any foam, if it exists, from under the v-berth). I'm actually hoping there isn't any (because it is a pain to remove). Carpy, with a 22 of my same vintage, just had a small "volcano" beneath the inspection plate* that is under the porta-potti, and none in the main area (IIRC) so I am hopeful.
Sunbeam
*Which of course means he had no real "flotation" provided by said foam.
It is possible to do calculations to find out just how much foam (or really "flotation" of some sort or another, it can be any form of trapped air, etc.) would be necessary to float the boat. Another step would be to figure out where to put the foam so as to have the boat float as near to level as possible (presuming that is desirable, but perhaps it does not matter). A seat of the pants guess tells me that the foam that may sometimes have been installed by C-Dory builders in the past at certain times did not take those calculations into account. It has also always been open-celled, from what I can tell, which means it's subject to soaking up water over time and thus becoming ineffective (I would use closed cell foam or some sort of air bladder(s) myself).
I realize that nothing I'm saying above IS a calculation (although there are calculations that can be performed), and I don't think anyone should do something they are not comfortable with on my advice. Basically, I have read a small amount on the subject (because there are folks who have calculated the amount and placement of flotation for their sailboats and I have read those articles).
If I did want positive flotation in my 22, I would be calculating it and then adding closed cell foam in the recommended amount and location. I suspect it would be spread throughout the boat (and thus taking up valuable-to-me stowage and cockpit lounging space). I'm fine with it the way it is (and plan to remove any foam, if it exists, from under the v-berth). I'm actually hoping there isn't any (because it is a pain to remove). Carpy, with a 22 of my same vintage, just had a small "volcano" beneath the inspection plate* that is under the porta-potti, and none in the main area (IIRC) so I am hopeful.
Sunbeam
*Which of course means he had no real "flotation" provided by said foam.
I just finished digging foam out of the berth area on our 19. The triangle section forward of the portapotty "nook" was already clear of foam and made into a nice storage compartment from the factory. Being under 20ft they must still have felt that foaming in the side sections under the berth was enough to make up for it. There is a fiberglass wall between that forward triangle and the side sections of underberth space. Also, most folks install hatches on the top and most use at least some form of highly water resistant hatch so even though these hollows could still take on water in a boat flooding, it would be slow and still provide floatation for a short while while it found its way in.
If you don't carry a dinghy already you could always use one of these for piece of mind. http://www.landfallnavigation.com/switlikmom600.html
We are planning to use a portabote for a dinghy so I may get one as an emergency out-of-the-cold-water platform for when we carry the dinghy folded up or not at all.
If you don't carry a dinghy already you could always use one of these for piece of mind. http://www.landfallnavigation.com/switlikmom600.html
We are planning to use a portabote for a dinghy so I may get one as an emergency out-of-the-cold-water platform for when we carry the dinghy folded up or not at all.
My 2009 model, CD 22, came direct from the factory with the three v-berth hatches and no foam. Maybe this was on the instructions of the previous owner, but I'm sure the factory would not let it go out if it was a safety issue. As previously mentioned, they are three separate compartments, doubt if the boat will sink if one got holed. Also I keep my inflatable securely lashed to the roof, if I do not have time to cut the ropes (knife stored in the cockpit) and use as a life raft, I'm sure it would contribute as a buoyancy aid.
Martin.
Martin.
I looked at a 2009 22 Cruiser before I bought my boat. It was built by Fluid Marine. It had three (nicely finished and bulkheaded) compartments below the V-berth and no foam. So my guess would be that's how they were built at that time. I would prefer if my 2002 had come that way.
Our 2012 CD22 does not have any foam under the V-berth, it is all open and finished with 3 hatches. The only place there may be foam is under a small portion of the port forward seat and under the floor in the cockpit. Everything else is open for storage. Seems like the newer boats do not have foam installed. I did not order the boat without foam and as far as I know this is the current way CD22s are built. If you are worried I like the air bag suggestion.
We did 3 hatches and love the extra storage. It was quite a chore to remove the foam. Our hatches have double latches and a rubber seal so I would think that we retain most of the flotation at least for a time. When you have the horseshoe shaped berth cushion out while you are doing the work, cut it into 3 pieces. It makes access a lot easier. Since you are going to the upholstery shop anyway remake the center cushion larger or add a small second section to the center cushion so that the bed does not have the notch.
I removed the foam and love the storage. I gave the "floatation" issue a lot of thought (2 years) before I did remove the foam.
The deciding issue for me was the chance of swamping / and or sinking. It's my understanding that most boat sinkings are the result of failure of a thru-hull and typically occur when the boat is left alone tied to a dock. Our boats don't have a thru-hull, so that greatest risk is gone. Second, I store it on the trailer. I concluded the risk was low enough that I was willing to take the chance. Other factors include that if it did float it would be upside down and bow only on water surface, & consequently, no self rescue.
Chuck
The deciding issue for me was the chance of swamping / and or sinking. It's my understanding that most boat sinkings are the result of failure of a thru-hull and typically occur when the boat is left alone tied to a dock. Our boats don't have a thru-hull, so that greatest risk is gone. Second, I store it on the trailer. I concluded the risk was low enough that I was willing to take the chance. Other factors include that if it did float it would be upside down and bow only on water surface, & consequently, no self rescue.
Chuck