TOPIC: Question for building a new floor! Foam or Air???

Okay I have a IMPORTANT QUESTION! When building a floor and sealing it perfectly does the builder want to install a drain or some type of access that allows one to get under the floor??? Example: Floor is 100% sealed with ZERO access and some how water gets inside with the stringers. What then??? Should one assume this will happen and build in an access point and drain??? Even with a foam filled hull water can still get in, I know the new foam does not hold water but water can still enter. Any thoughts.... Seems like it would be better to glass in the stringers REAL GOOD and have the bottom side of the floor glassed in before insulation and once installed glass the top side of the floor with mat and cloth REAL GOOD and have it extend up the sides of the hull but leave between the stringers hollow and leave a way to release the water. I notice a few of my boats have a drain tube for the splash well, a drain tube above the floor line and another drain tube that is under the floor. What if water finds a way against all odds, sounds crazy but what if when picking up the bow on the trailer and lowering it back down you can hear running water inside the hull after the floor is built and done with zero access??? Thanks, Mike

I figure that water WILL get in there eventually- There's just no way around it...

When I replaced the floor in my Glasspar, I added an access hatch to it under the splashwell- This is before I glassed it-



As it came from the factory, the only access to the bilge area under the floor was the plug in the transom- Now I've got a way to get in to pump water out, or a place to add a bilge pump if I want to.

Any body else have any thoughts on this???
Where can you buy composit stuff that will not become rottin in 20 years anyway? Mike

In my opinion you should always leave an opening for water to drain and air to flow. What rots the wood is wet wood STAYING wet. I've seen boats 50 years old with perfect floors, transoms, and stringers thanks to always draining the water from the boat after use, always having the boat covered by a roof or breathable cover, and always having a way for the inner floor to air or dry out. No matter how hard you try to seal it up, water WILL get in there so there needs to be a way for it to escape and breath.

Doug

Im not a fan of foam for various reasons but these guys are spot on...

Water will eventually find a way under your floor, one way or another...no matter how well you seal it up. Even if you did manage to seal it perfectly, as you use the boat, its going to flex and when it does, its going to start to develop areas that are going to let water under your floor. If its sealed well, it will trap that water down there and the wood will stay wet allowing it to rot.

I am however a big fan of leaving openings or access hatches to under the floor...this is why i left a big opening next to the transom, similar to what Andgott shows when i did the floor on the Performer...that way, when water does find its way under the floor, it will have plenty of ventilation so that it can properly dry out. Gives you plenty of room to put a bilge pump in there too and also gives you access to the bottom of the hull for inspection purposes.

My thoughts go back 35+ years when I lived in northern MN. An average 7 year old boat needed some wood replaced, if you got 10 years you're doing very very well.

Now...I've de-boned a Manta Ray and am replacing all the wood bones with expanded PVC foam sheet. The Ray has a small raised deck under the bow that forms a void. The original deck, 3/8" plywood covered with resin on the outside was rotted away inside, even with drain holes. Tomorrow, weather permiting, I'll fill the new void with foam before installing the new deck. Replace the air with foam...no air means no moisture...no mold...no rot...no holes...no insects...no reptiles...no mammals...no clogs...no worries.

I picked up the PVC sheets a few blocks from the house at a Piedmont Plastics location www.piedmontplastics.com/locations.asp