Which type of foam allows water to move through the wall more easily?

Open-cell foams are designed to have a structure that creates interconnected cells. This configuration allows water and moisture vapor to move more freely through the material. The open structure means that air and moisture can pass through more easily compared to closed-cell foams, which are impermeable to water and have a denser cell structure that blocks the movement of water.

Using open-cell foam in wall assemblies is beneficial in situations where moisture vapor control is necessary, as it can help manage humidity levels and reduce the risk of condensation buildup within the wall. The permeability of open-cell foam can facilitate drying if moisture does infiltrate the wall system, enhancing the overall durability and performance of the building envelope. Other foam types, such as closed-cell foams, restrict moisture movement, which can be a disadvantage in specific applications where moisture management is a priority.