Caulking

Caulking is used in a wide variety of applications in both residential and commercial properties, as well as boats and some recreational vehicles, as a means to secure glass, metal, and other components, as well as weatherproof doors, windows, and seams, for patching and repair work, and to add insulation value in small cracks or gaps in buildings and other structures. Resembling thick toothpaste in texture, caulking is usually applied using a special caulking gun, masonry knife, or other tool, to ensure a strong bond between the caulking material and the structure being caulked. Caulking is also widely used in residential and commercial construction in the application of drywall and paneling, and is often used to finish off trimwork around the walls, ceilings, and windows of a room. By sealing small gaps or cracks, caulking also adds stability and dampens sound transmission.

There’s no doubt that caulking is highly useful in the construction trades. It’s also one product which is very easy for homeowner’s to use in do-it-yourself projects, such as bathroom tub caulking and in winterizing windows. And today, the caulking products which are on the market in the United States are safe, by and large. But there was a time when the caulk itself was potentially more dangerous and harmful than the leaks and drafts it was used to prevent.

Caulking and asbestos

Before safety rulings made its inclusion in construction materials illegal in the late 1970s, asbestos made up about 25% of the majority of caulk used in residential and commercial buildings, and other applications, here in the United States. Composed of millions of tiny, pliable fibers and offering superior fire resistance, strength, and insulative properties, asbestos seemed an ideal ingredient to add to caulk. And when first applied in its semi-liquid state, it was essentially as harmless as any other caulking material. However, over time and especially with exposure to the weather, air, and other environmental elements, caulking of any material breaks down and flakes away, requiring removal and re-caulking. The removal process generally involves scraping or chipping the old caulking away from the substrate, which results in tiny particles of caulking material being released into the air. Moreover, even without repair or removal, as the material naturally degrades small fibers may be released into the air, especially when caulking is used around window or door seams which are subject to opening and closing.

Last modified: December 09 2009.