Polyurethane caulk is a highly durable caulk that is often used in place of silicone caulk. This sealant is known for its ability to adhere to several types of materials, so it is often recommended for creating seals between two different surfaces. Seals made with this caulk can last decades, but working with the caulk can also present some disadvantages, such as stickiness, stiffness and toxicity. Many people choose to use another caulk for indoor projects, but those who want to do a bit of outdoor caulking can benefit from using polyurethane caulk.
This type of caulk is a versatile sealant, and it can adhere to various types surfaces. The caulk can be used on plastic, glass, concrete, metal or wood. It can be particularly useful on wood, because it can withstand scuffing and other physical stresses well. In addition to its application versatility, some people claim that it has an incomparable stretching ability, which can be beneficial for use with materials that are expected to expand and contract regularly. After it is dry, the caulk can even be painted to help it blend into its surroundings.
Applications of polyurethane caulk can last a relatively long time. Users of it can expect seals to remain functional for 10-20 years. Some people say that polyurethane caulk resembles putty. It's sticky, and many people find using this sealant to be a bit messy. Mineral spirits can be necessary for its tooling.
The disadvantages of using this kind of caulk include its stickiness, its stiffness and its toxicity. Some users have reported difficulty squeezing the caulk from its tube, and some people have resorted to using heat in an effort to ease the caulk out of the tube. The application process can also require the use of protective materials, such as gloves, in order to minimize the chance that the user will harm himself or herself. The caulk is solvent-based, so users might have to use paint thinner for clean-up purposes.
Polyurethane caulk can be the best option for outdoor work, but it might not be the most practical choice for indoor modifications. For many indoor projects, acrylic latex is often considered to be the better choice. Users should be aware that removal of polyurethane caulk can require a lot of work — homeowners might have to sand or cut the caulk off of the surface to which it was adhered. It can be a bit more expensive, but polyurethane caulk can be a sound investment for those who want to use a durable caulk for exterior work on their homes.