Герметики и заделка швов: от судостроения до строительства.

Flexible material used in construction to seal joints
the studs installed on horseshoes

Caulk or caulking is a material used to seal joints or seams against leakage in various structures and piping. The oldest form of caulk consisted of fibrous materials driven into the wedge shaped seams between boards on wooden boats or ships. Cast iron sewerage pipes were formerly caulked in a similar way. Riveted seams in ships and boilers were formerly sealed by hammering the metal. Modern caulking compounds are flexible sealing compounds used to close up gaps in buildings and other structures against water, air, dust, insects, or as a component in firestopping. In the tunneling industry, caulking is the sealing of joints in segmental precast concrete tunnels, commonly by using concrete.

Traditional caulking (also spelled calking) on wooden vessels uses fibers of cotton and oakum (hemp) 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". Those who carried out this work were known as caulkers. In the Hebrew Bible, the prophet Ezekiel refers to the caulking of ships as a specialist skill.

In riveted steel or iron ship construction, caulking was a process of rendering seams watertight by driving a thick, blunt chisel like tool into the plating adjacent to the seam. This had the effect of displacing the metal into a close fit with the adjoining piece.

Caulking of iron and steel, of the same type described above for ship's hulls, was also used by boilermakers in the era of riveted boilers to make the joints watertight and steamtight.

For bulk use, caulk is generally distributed in disposable cartridges, which are rigid cylindrical cardboard or plastic tubes with an applicator tip at one end, and a movable plunger at the far end. These are used in caulking guns, which typically have a trigger connected to a rod which pushes the plunger, and has a ratchet to prevent backlash. The push rod may also be actuated by a motor or by compressed air. Similar mechanisms are used for grease guns. For smaller applications, caulk may be distributed in squeeze tubes. Closed cell rod will also lose firmness and out gas if damaged during installation or overcompressed or at sharp bends. The gasses cannot pass through this backer rod and can deform, weaken, and even cause holes (leaks) in the caulk or sealant as it escapes. Out gassing is the reason that open cell backer rod was developed.

The most common type of caulk is acrylic latex, for general purpose use. Not only is acrylic latex inexpensive, but it is also the easiest type to apply smoothly and later paint if needed.

Acrylic tile sealant usually comes in small tubes and is commonly used for wet applications.