Acrylic Caulk vs. Silicone Caulk

Caulking around the base of a toilet.

Acrylic caulk and silicone caulk have very different qualities and are designed for specific purposes. Caulking has many applications, and these products are designed to meet these separate needs.

Caulking can be applied to seal cracks in painting applications, for prevention against moisture, and lastly, to insulate against cold air coming into a house, or hot air from leaving a house.

Acrylic or Silicone Caulking

For most caulking applications, homeowners will either use an acrylic latex caulking material or one made from silicone compounds. Acrylic caulking is more popular because of its ease of use and because it cleans up well. It also provides a clean, neat seal.

This caulking works very well for painting applications as it fills any gaps between walls, ceilings, and woodwork trim. It can also seal gaps around windows, doors, and electrical switch plates, preventing heat loss and guarding against cold drafts. Although acrylic caulking can be used to guard against water penetration, due to its propensity to shrink and distort over time, it is not the best choice.

Silicone caulk, often referred to as rubberized silicone caulk, remains flexible for most of its lifetime without peeling, cracking, or distorting. It will maintain and keep a waterproof barrier against moisture much longer than acrylic caulking as a result.

This trait makes silicone the caulking of choice around showers, bathtubs, sinks, and toilets. Additionally, due to its long-lasting nature and its ability to retard moisture and maintain its strength, silicone caulking is an excellent choice for outdoor use and for protecting the home from outdoor wet-weather conditions.

It should be noted that due to silicone caulking’s moisture repelling feature, paint will not adhere to it.

Applying Caulking

The main purpose to applying caulking is to fill a gap. Although bathrooms, kitchens, and most outside applications require silicone caulking, and interior applications require acrylic caulking mostly for sealing unsightly gaps, most of the same rules apply for applying either of these.

Be sure to cut the tip of the caulking gun at a 45 degree angle and the right size for the appropriate application. Usually cutting the tip smaller rather than larger will produce better results, but the tip can always be cut larger if initially cut too small. This will eliminate messy clean up, save material, and allow a neat, small bead of caulking to be applied.

Apply a small bead of caulking evenly and swiftly. Plan on layering the caulking through multiple passes, rather than using big globs all at once. Whether using acrylic or silicone caulking, clean up will be quicker and easier when there is less spillage to worry about, so also clean and wipe as you go. Have sufficient scrapers, cloths, or rags to wipe caulking into place and remove excess.

You'll also want to keep the area, tools, and equipment clean as the job progresses. This will ensure professional results and limit cleaning time to a minimum.