foam filling and below deck drainage system theorycrafting

[Smeag]

so i've been thinking (way too much time thinking) about the design of my drainage system and the foam i'm gonna put under my deck in my bowrider restore.

I'll start off with the foam. i had an interesting idea to put some sort of drainable type material on the bottom. think crushed up packing peanuts or something -- maybe 2 inches or so lineing the bottom of the hull. the idea would be to pour foam over top of this. this would be similar to a gravel drainage system. little cracks and a place for water to drain down into. the water would collect on the bottom and when the boat is tilted or what not the water would be able to run to the back of the boat and drain out.

i have even toyed around with the idea to have 2 drainage holes(from the stringers) in the bilge with plugs in them. the idea for this that you can drain the water out of the bilge and then pull a side plug. if you see water drain out you would have a general idea of which side of the boat the water is coming from. this would also eliminate leaving open gaps for water to run into those stringers from the bilge. essentially creating a sealed off compartment, but also a system for letting water drain out if it should ever get in there.

so i may be making this way more complicated than it has to be but it seems like a solid idea to me . let me know your thoughts.

 

[SuzukiChopper]

Re: foam filling and below deck drainage system theorycrafting

Well, I think you're going to end up having to experiment with your ideas. They sound good in theory but there may be issues. I know you said some kind of drainage material, and I see where you're going with it but keep in mind that whatever you chose shouldn't be affected by heat. The 2 part pour foam does generate some heat. The other thing you need to consider is the viscosity and working time of 2 part pour foam.

I would get some pour foam and some samples of whatever material you come up with (hopefully more then one) and go buy some 5 gallon buckets. Put down your drainage material and then experiment with the pour foam. Once the pour foam is set, cut the thing apart and see if your theory still holds. I'm thinking that the pour foam is going to just end up bonding all your drainage material together anyways. Maybe peg board over top of the drainage material would solve that issue?

 

[capri1600]

Re: foam filling and below deck drainage system theorycrafting

I dont like the packing peanut idea. Think about why the foam is there. It's for in the event that you have an accident or some sort of damage and are taking on water. If this happens the breach could cause the peanuts to spill and then you sink. There's the environmental consideration too. I'd hate to have an incident and then on top of that spill all those styrofoam pieces into my favorite body of water.

 

[SKEETR]

Re: foam filling and below deck drainage system theorycrafting

I have an aluminum boat so I'm not too concerned about stringer damage. However like alot of us my boat is backed up into my driveway and if any water gets into the boat during winter it ends up in the bow. Replaced my deck this year and had standing water in the bow. Supprisingly the water did not penetrate the foam. Aside from about 1/8" on the surface it was dry as a bone on the inside.
What I was considering, if it was necessary to replace foam, was taping down some additional ribs of 1/2" landscape drip tubing cut in half. This, I was thinking, would provide some capillary action during deck washdown. I suppose one could use pvc over the stingers. My prefference would be the 2" red stucco tape.

 

[stackz]

Re: foam filling and below deck drainage system theorycrafting

why not compartmentalize between the stringers and then completely seal the compartments that you are going to fill with foam??

you can use pvc pipe going the length of the compartment and seal it on both sides of the compartment for "thru-drainage" and then just fill and forget that compartment after you seal it to the boat floor completely.

saw this on one of the completed restoration threads. I think it was the 1988 22' center console one?

I really liked that idea and is what I'm going to do.