Latex and silicone caulk are the most common types. The two materials are sometimes combined and sold as siliconized latex or latex plus silicone. These products offer the easy use of latex with the added durability of silicone.
1. Acrylic Latex. Acrylic-latex caulk, also known as latex or general-purpose caulk, is water-based and provides excellent adhesion to most common building materials, including wood.
Acrylic Latex Caulk *Plus Silicone - In my opinion this is the minimum standard of sealant that should be used for interior painting project applications such as the joints where baseboards, door & window casings, and crown moldings meet the walls.
Silicone caulk stands up to extremes in temperature changes and can last up to 20 years when properly applied. Cleanup for silicone caulk requires solvents instead of water. Used outdoors in areas exposed to direct sunlight or rain, silicone helps the seal last longer.
Removing the old caulk and replacing it with a new bead of caulk instead usually creates a better seal. However, you can effectively caulk over caulk as long as the bottom layer of caulk isn't damaged or moldy. The old caulk should also be clean, dry, and free of oil for the best adhesion.
In general, sealant is the prefered sealing solution for bathtubs and showers, as it is more water resistant than traditional caulk. Silicone sealant forms a watertight seal that is resistant to heavy temperature changes.
DAP Dynaflex 230 Premium Elastomeric Sealant
Its formula is specially designed to resist cracking and improve flexibility over other latex-based caulks. After application, it should be ready for painting in about 2 hours. During the test, we found Dynaflex 230 very easy to apply.
For a tough, watertight, mildew-resistant seal, we recommend using Loctite 100% Silicone.
The Best Silicone Sealant Overall—Gorilla Clear Silicone Sealant Caulk. This Gorilla sealant is made of pure silicone and is excellent for any heavy-duty or touch-up project. The sealant is waterproof and can be used in both indoor and outdoor applications.
Caulk makes your surface airtight and watertight. Silicone sealants, on the other hand, remain flexible for years which make them ideal for areas that are prone to expansion and contraction. Silicone has strong binding properties that can be applied to almost any surface both indoors and outdoors.
What kind of caulk do you use in the bathroom? The best caulks for tubs, sinks, or shower stalls come in tubes labeled “Tub and Tile” or “Kitchen and Bath.” These are either acrylic latex or silicone compounds that have been chemically tweaked to resist mildew and to stick to smooth, nonporous surfaces.
Acrylic Caulk (also known as latex caulk)
It is easy to work with, and you can smooth the joints with your finger to create a clean finish. Old acrylic caulk is easily removed – just cut it with a utility knife or pull it.
The most popular and versatile type of caulk is acrylic latex caulks, also frequently referred to as painter's caulk. According to Home Depot, you should use acrylic latex caulk for sealing holes or gaps in drywall, wood (furniture, baseboards, etc.), or masonry-related projects.
A line of caulk (called a "bead") should be no thinner than ¼." Thinner beads shrink while drying, creating too thin a seal to tool or seal properly.
We recommend using a latex-acrylic caulk with added silicone. Latex-Acrylic-Silicone caulk products are available in different colours to better match flooring or baseboard paint colour. They adhere well to wood, MDF, and composite baseboards and have enough flexibility to minimize cracking.
New caulk doesn't stick to old caulk, so if you fail to remove the old stuff, the new caulk can't form a watertight seal, leaving the potential for moisture to seep into areas where you don't want it. The best way to remove caulk is through a combination of chemical caulk remover and manual tools.
While caulk alone can be applied to narrow cracks, gaps wider than 1/4” should be filled with foam backer rod first. These flexible foam tubes are available at building supply stores in several diameters.
While latex caulk is less expensive and easier to work with, silicone is more durable under extreme weather conditions, and can be used as a binder as well.
Silicone caulk is excellent at water sealing and flexibility so it has its place in construction. There are two main places it never should be installed, wood or any painted surface.
Sealing joints on a damp surface should be strongly avoided, since silicone sealants generally do not adhere as well to moist substrates. If you want durable joints, never apply sealant in rain, freezing rain, snow or heavy fog.