Q: I read about the wonders of rubber-based sealant as an alternative to silicone, but are there applications where this type of product would not be a good choice?
A: A co-polymer rubber-based sealant such as Lexel offers superior adhesion that creates that 100-percent watertight seal, can even be applied to wet surfaces, and it readily accepts paint. For watertight applications it makes an excellent choice. However, for paint-grade finish carpentry applications where the caulk bead might need to be sanded into shape, the sealant’s high adhesive properties and rubber consistency make it very difficult to sand smooth once it has dried.