Aaronhoy,

As a rough estimate, and judging by the core thickness, if your ENTIRE core became saturated it could probably double the weight of your hulls. However, completely saturating all of the core material in a boat would be a rare instance for sure. The point here is that the weight gain from water could be very significant while your hulls appear completely dry inside and out.

As for why it is (may be) occurring only at the stern. This requires some visualization of "wicking". If the leak is near the stern, the water will enter there slowly and persistently. The actual leak can sometimes be very, very small. The water wicks in at that location and then spreads out. This is the chemical nature of water (look up osmotic and oncotic pressures/gradients for more understanding). Without sounding too dramatic, this kind of water intrusion can be a boaters` nightmare. It is the number one reason bigger boats are usually surveyed before being purchased. A boat may look great in every sense, but be a disaster because of this unseen problem. I have been a powerboater for years, and this is the one worry that can keep me up at night.

I do not know how commonly core H2O penetration occurs with the H16. I know the H16 is, in fact, a cored construction. Therefore, it can happen. But, since these boats are generally stored on land, it must occur to a lessor degree than boats that reside in the water.

Dave