People use the terms caulk and sealant pretty much interchangeably, and they are both used to fill gaps, but they’re actually designed for completely different jobs. Let’s have a look at the difference, and when you’ll want to use them.
When should you use caulk?
Caulk is generally used for decorative work around the home on interior trims like skirting boards, where small gaps need to be filled before painting. One of its main advantages is that it can usually be painted once it’s dry, which makes it ideal for creating a seamless finish between surfaces. It’s important to remember that caulk isn’t designed to withstand constant exposure to water, so it’s not really the right choice for bathrooms, showers or sinks.
When is sealant the better option?
Sealants are made to create a durable barrier against water, air and moisture, so they’re what you’ll need to use for bathrooms and kitchens, and other damp areas. A proper bathroom sealant, for example, is typically used around baths, shower trays and washbasins to help prevent leaks and water damage. Loads of modern products like these examples https://www.ct1.com/product_application/sealing-your-shower-tray-with-bt1-bathroom-sealant/ are made with anti-mould properties, which make them suitable for really humid environments like showers.
So, while sealants are usually more difficult to paint over than caulk, they’re much better in terms of flexibility and water resistance. In most cases, the choice pretty much comes down to the environment you’re decorating. For decorative filling in dry rooms, caulk is the winner, but for waterproof protection, sealant is the best solution.