I know the topic of flotation has been discussed numerous times. However, after reading "Gerts" comments in the Designs/Plans section, it reminds me of the importance of flotation.
First off, I am "by no means" an expert in boat construction. Heck, it has taken me three years to reach the point where I am finally ready to put the decking on my 15' runabout. Before, I do that it seems like this would be the ideal time to add some flotation.
My two cents worth:
Just because most small wood boats won't sink, doesn't mean that floatation is not needed. As Gert pointed out the "Shearwater" design didn't sink but it could not be bailed.
Especially in cold water, being stuck hanging on to your boat is potentially tragic.
My observation is that a great many builders (of small boats)do not add the flotation. I am not sure why, but maybe its because we all figure it will not happen to us.
As I mentioned above I know that this subject has been discussed before. But there does not seem to be much concensus of ideas. In fact, some of the ideas seem like they could be downright dangerous.
I have seen floation ideas ranging from ping pong balls, fun noodles, styrofoam, air bags and sealed compartments. Obviously every method has its pros and cons.
My own (again not expert) ideas are that styrofoam is the most readily available but is not acceptable if petroleum is on board. Ideas like ping pong balls are not very effective as they waste too much valuable space to match the effectiveness of solid foam. Sealed compartments can be a problem if they are damaged in the event that causes the boat to capsize.
So after much thought I am considering buying the two-part foams available from some marine supply houses. I think these are usually urethane, but I am not positive about that. I am not sure it is a good idea to pour these foams directly into voids in the boat as I think that might promote rot due to lack of ventilation. Therefore, I am thinking about casting my own foam blocks in a separate container and cutting them to fit various suitable spaces in the boat. The only thing I haven't figured out is how to secure the foam so it doesn't float away when it is most needed!
Sorry if I have rambled on here. But with all the expertise on this Forum, I think more discussion would be valuable. I know I would appreciate it.