The terms "caulk" and "sealant" are interchangeable and the products serve an identical purpose. Water-based caulks are one of many different types of caulk products. These caulks, which are water resistant, are ideal for use in areas that receive rain or remain wet for extended periods. Caulk fails because the incorrect type is used or because the caulk eventually cracks as the gap it was used to seal was wider than 0.5 inches. For this reason, always use the correct caulking product for water-resistant applications.

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Water-resistant caulks are suitable for use in outdoor areas.

Water-based Caulk in General

These caulks are often termed latex sealants or caulks and are simple to use because they are paintable, apply easily and give off little odor. Water-based caulks normally contain a mildewcide as their prime function is to seal materials that either remain wet constantly or are exposed to moisture on a frequent basis. These wet and damp areas represent the ideal condition in which mildew can grow. This caulk is available in squeeze tubes that range from 4 to 6 oz. and also in the larger cartridges that range from 10 to 12 oz. Water-based caulk is normally crack resistant and flexible. As in the case of other latex caulks, these apply easily and are nonflammable. Water-based caulks are available in a number of colors.

Acrylic Latex Caulk

This water-based caulk is more flexible than the vinyl latex caulks. It is nonflammable and adheres to most surfaces in pigments that match the materials or surfaces to which it is applied. Acrylic latex caulk remains effective for up to 15 years. It is flexible and maintains this elasticity for life. Latex caulks can be applied in extreme temperatures and can withstand rain almost immediately.

Silicone Caulk

This caulk is used in showers, bathtubs and sinks as it is totally water and mildew resistant and provides the best adhesion to smooth surfaces, such as metal and glass. Silicone caulk is not affected by ultraviolet radiation and remains flexible. Silicone caulk is also nontoxic and can effectively be applied at any temperature.

Siliconized Acrylic Caulk

This caulk combines silicone with acrylic latex formulas for improved water resistance. The caulk can withstand more movement than what acrylic latex can and is available in a variety of colors. Siliconized acrylic caulk has a lengthy life expectancy of up to 35 years. It is also mildew resistant, and, like the latex product, can withstand rain almost immediately.

Synthetic Rubber Caulk

Synthetic rubber caulk is an extremely flexible caulk that is ideal for exterior use on joints that are continually expanding and contracting. This caulk can be applied in adverse weather, such as rain, and stretches very easily.