Tips for Removing and Reapplying Caulk and Sealants
Is it time to remove and reapply the caulk or sealant around your tub, window or sink? Caulk and sealants do have a lifespan and sometimes it’s very obvious when they’ve lost their effectiveness. Ensuring the integrity of the protection these polymers provide is important to keep joints and seams well-sealed.
Types of caulk/sealants
The basic difference between caulks and sealants is the level of elasticity. Caulk is more rigid when it’s dry, whereas sealants have more “give.” The most common types of caulk/sealants include latex (very durable and used for drywall, wood and masonry), acrylic (great for painting but not as long-lasting when exposed to a lot of water), silicone (popular sealant offering flexible waterproofing around windows and in bathrooms) and butyl-rubber (good for outdoor projects like roofing, gutters and siding). Caulk and sealants are available in regular or fast-drying varieties as well as narrow or thick peel and stick tape if you’re not as adept with a caulk gun.
Out with the old
There are a couple options to remove old caulk. (And don’t skip this step by just layering new caulk over the old.) Depending on the type, it may be as easy as using a putty knife to loosen the bond and then pulling out the length of caulk with a little bit of scraping to remove remnants. Other methods involve carefully cutting along the edge of the bond with a utility knife and using a putty knife, caulk remover tool or bristle brush to remove all the bits.
To loosen old caulk, heat it up using a hair dryer on its lowest setting, working a few inches at a time. Or use chemicals like Goo Gone, WD40 or nail polish remover to help break the bond. But be sure to test chemicals in an inconspicuous spot first to ensure they don’t leave a stain. And be very careful with utility and putty knives not to scratch surfaces.
Once the majority of old caulk is removed, get some good ventilation going (if you haven’t already) and clean the area with ammonia-free cleaner and scrub with bleach if the caulk residue was moldy, then rinse and dry. Use rubbing alcohol to remove any trace of caulk and cleaning agents and dry the area thoroughly.
In with the new
Unless you are very confident with your ability to apply a beautiful line, painter’s tape can be helpful to keep the caulk where you want it. Trim the tip off your cartridge or tube of caulk either at a 45 degree angle or straight across if your seam involves lots of corners or obstacles. The less you cut from the tip, the smaller your line, which minimizes waste when you smooth it into the joint. Using a caulk gun helps you apply steady pressure at a consistent speed. And if you can’t go the entire length of the seam without stopping, to avoid a big glob where you stop and restart, begin at the other end to more neatly join the two lines together.
Smooth the line with a wet finger, a tool or a damp rag, then carefully remove the tape and fix or wipe off mistakes. Wait the appropriate amount of time before painting the caulk or subjecting it to moisture or temperature changes.