Groundwater & Basement Water Intrusion in Kaneohe, HI

It is a Hawaii-specific method in which vertical boards form the structure and the finish at once, with no studs, cavity, or sheathing. It matters because there is nothing to hide damage and nothing to protect the interior. Water entering the assembly wets the single layer through, and it shows on both faces. Drying is quicker than a cavity wall because there is nothing enclosed, but replacement is more involved, since the damaged board is also the structure.

Probably not with the house. On the windward side of the Koolau the rain is close to continuous and the humidity stays high year-round, so materials do not get the dry interval that a seasonal climate provides. That means a repaired leak does not automatically lead to a dry assembly, and mechanical dehumidification often has to do work that the weather does elsewhere. Judging by meter readings rather than by feel is especially important here.

It helps a great deal by keeping the floor structure up off ground that stays wet, and it introduces its own requirement. The space under the house has to stay ventilated and free of stored material, and the piers and the girders they carry need to be inspectable. Where that space has been enclosed for storage or an added room, the advantage disappears and the framing sits in still, humid air. Keeping it open is the point of the design.