February is a great time to check your bathrooms tubs, showers, and sinks for cracked or missing caulking. Water leaking under tubs or base cabinets can cause unseen damage to the infrastructure of your home. Over time, seeping water can corrode base flooring or even structural wood in your home resulting in big reconstruction projects.
Although it may be tempting to caulk over old caulking that is deteriorating, it is important to take the time to remove all old caulk first. There are several reasons that this step should never be skipped. For example, if you are recaulking because the previous caulk is stained with mildew or mold, recaulking on top of it means it will continue to grow underneath. If your old caulk is shrinking, it is only going to continue to do so and will quickly break the seal of the new caulk and cause it to separate as well.
Caulking must always be applied to surfaces that are clean and dry. You will need to remove all of the dirt, dust, debris, paint and grease that is on the area to be caulked. If you have previously removed silicone caulk from the area, you need to ensure all of its residue has been completely removed.
You can clean the area you are caulking with a rag and some rubbing alcohol or a disinfecting spray, then rinse thoroughly with water and dry it completely.
Not all caulks are suitable for all recaulking jobs. These days, many manufacturers are putting job specific labels on their caulking products. However, you will need to have a basic understanding of the different materials you might find before you shop.
Rubber caulks are often used for aluminum and asphalt, while latex caulks are used for utility caulking. Silicone caulk is the material of choice for sealing in bathrooms and recaulking exterior trim. It can also be used against glass, aluminum and other non-porous materials. Polyurethane is best for concrete, masonry and exterior caulking around doors and windows.
If you are caulking in an area where the caulk might show, keep color in mind. A clear caulk is good for surfaces like brick, while gray caulk can be a good choice for concrete floors. Keep in mind that some caulk varieties, such as elastomeric caulk, may look white when applied but will dry clear.
At minimal cost and a bit of time you can easily repair the caulking yourself with a trip to the hardware store. There are many how to guides on the internet to help you through the process, such as this one.