Caulking

Caulking is both the processes and material (also called sealant) to seal joints or seams in various structures and some types of piping. The oldest form of caulking is used to make the seams in wooden boats or ships watertight, by driving fibrous materials into the wedge-shaped seams between boards. A related process was formerly employed to join sections of cast iron sewerage pipe.

Caulking is also the term to describe the process used to make riveted iron or steel ships and boilers watertight or steamtight.

The same term also refers to the application of flexible sealing compounds to close up gaps in buildings and other structures against water, air, dust, insects, or as a component in firestopping. In the tunnelling industry, caulking refers to the sealing of joints in segmental precast concrete tunnels, commonly by using concrete.

Historical uses

Wooden shipbuilding

Traditional caulking (also spelled calking) on wooden vessels uses fibers of cotton and oakum (hemp fiber soaked in pine tar). These fibers are driven into the wedge-shaped seam between planks, with a caulking mallet and a broad chisel-like tool called a caulking iron. The caulking is then covered over with a putty, in the case of hull seams, or else in deck seams with melted pine pitch, in a process referred to as paying, or "calefaction"

Caulking (video games)

Caulking is a process used in video game level creation or editing (or mapping) for the generation of a level, or map, that when compiled is less demanding for the computer's graphics card to render in-game than it would be otherwise. A surface that is marked with caulk is not drawn in-game, and is commonly shown as bright pink within the map editor.

Inevitably, certain sides of some objects (e.g. walls) in a game scene will never be visible to the player during normal play. The person making the map can apply the caulk texture, instead of a normal texture, to these surfaces when building the map. The surfaces become invisible in-game and if compiled into a Binary Space Partitioning-File (or BSP-Level) they will also not be added to the list of Leaves (or convex polygons). The resulting reduction of polygons and textures used in the video game level reduces the required video card resources, possibly making the map smoother to play. In the case that a surface which was not meant to be visible inadvertently becomes visible, possibly due to a mapping error, some game engines support drawing caulked surfaces using flat shading.