What material do termites not consume, but will tunnel through to access wood in structures?

The material that termites do not consume, but will tunnel through to access wood, is foam insulation. Termites are primarily wood-destroying insects and prefer cellulose, which is found in wood. However, they can be found tunneling through foam insulation because it provides a barrier to reach their food source while not being a material they eat.

Foam insulation is commonly used in construction to improve energy efficiency, and its structure allows termites to create tunnels that lead them to wooden structural components. In contrast, other materials listed, such as gypsum board, plastic sheeting, and concrete, are less conducive to termite tunneling due to their density and composition. Gypsum board contains cellulose and is thus a potential food source; plastic sheeting and concrete are not biodegradable and would not provide any nutritional value. Therefore, foam insulation is the most accurate choice regarding termite behavior.