How To Choose the Right Caulk For the Job

Which Sealant is the Best?

There are a lot of options in the caulk aisle, and trying to spot the little differences on the label can be tough if you don’t know what you are looking for. This will help you make sense of those ever-expanding choices and choose the right caulk for specific jobs.

What Are the Most Common Kinds of Sealants?

These types of caulk dominate the shelves at tool supply stores. Labels don’t always tell you what’s in the tube, so we’ve included examples of each type of sealant.

Acrylic Latex

Acrylic latex caulks are the easiest to apply and smooth out. They’re also the only sealants that clean up with water. Look for versions labeled “siliconized” or “plus silicone.” Adding silicone to acrylic latex improves adhesion and flexibility.

Polyurethane

Poly caulks are generally tougher than other sealants, making them a good choice for driveways and other areas that take a beating. But their gooey consistency makes them hard to work with. Check the label before painting; you may have to wait several days.

Solvent-Based

Many solvent-based caulks are great for roofing because they don’t degrade in direct sunlight and can be applied to wet surfaces. But they’re gooey and hard to apply neatly.

Hybrid

Most hybrid caulks combine silicone and polyurethane for top-notch adhesion, flexibility and longevity. They’re easier to apply neatly than polyurethane but not as easy as acrylic latex. Most aren’t labeled “hybrid,” so we’ve pointed out the hybrids in the various photos. Cost is a clue: High-quality hybrids are usually the most expensive caulks on the shelf.

What is “Big Stretch” Sealant?

Latex caulk is typically less flexible than other caulks. Adding silicone helps, but Sashco achieved tremendous flexibility with its latex-based Big Stretch product without the addition of silicone. Big Stretch stretches up to 500 percent its original size. That’s impressive!

What is the Best Caulk for Siding and Trim?

Choose a hybrid or polyurethane

On a home’s exterior, high-quality caulk is critical—it locks out water, protecting homes against rot and peeling paint. Although some inexpensive acrylic latex caulks are rated for exterior use, we recommend hybrid caulks because they offer better adhesion and flexibility. For matching the appearance of materials like stucco or rough-sawn wood, we like Vulkem, a textured polyurethane.

Hybrid sealants: DAP 3.0 Window, Door, Trim & Siding
Polyurethane sealants: Vulkem (for texture)

What is the Best Caulk for Painting?

Choose acrylic latex

For just a couple of bucks you can find a caulk that dries fast, is easy to work with, easy to clean up, and can handle a little movement. Alex Plus is one good choice, but there are several others. If you are dealing with a large recurring crack in a wall corner or in a crown molding joint, choose a product with better flexibility such as a hybrid formula or Big Stretch acrylic caulk.

Latex sealants: Alex Plus, Big Stretch (for large cracks likely to move/open)

What is the Best Caulk for Kitchens and Bathrooms?

Just check the label

Caulk in bathrooms and kitchens is often visible, so choosing a product that’s easy to apply neatly is important. It also needs to be waterproof and mold and mildew resistant. Choose a product labeled with those traits. Acrylic latex kitchen and bath caulks are the easiest to work with, but hybrids generally have a longer life span.

Hybrid sealants: AMP Kitchen and Bath Sealant
Siliconized acrylic latex sealants: Kwik Seal Ultra, Loctite Tub & Tile

What is the Best Caulk for Concrete and Masonry?

Choose a specialty caulk

A caulk specially formulated for concrete and masonry will outperform general-purpose products. Most masonry and concrete sealants are polyurethane or hybrid formulas. But one acrylic latex product, Slab, also performs well, especially on concrete cracks that move a lot. Some concrete and masonry caulks are self-leveling and can be used only on level surfaces.

Polyurethane sealants: Loctite PL Concrete Sealant
Hybrid sealants: DAP 3.0 Self-Leveling Concrete Sealant

What is the Best Caulk for Roofs?

Choose solvent-based sealants

Any caulk that lives on a roof is going to get hammered by the elements. Roof repair caulk needs to be able to survive extreme exposure to sunlight and temperature variations yet remain flexible. These two recommended products can actually be applied on wet surfaces!

Solvent-based sealants: Lexel, Through the Roof

What is the Best Caulk for Gutters?

Go with a hybrid or solvent-based product

It’s no surprise that a product designed to seal gutters needs to be 100 percent waterproof. But it also needs to be tough—tough enough to handle the abrasion from debris and ice in colder climates. Most gutter sealants do a good job on metal, but not all will adhere to plastic gutters. Be sure to check the label.

Solvent-based sealants (for metal or plastic): Lexel
Hybrid (metal only): DAP 3.0 Gutter & Flashing

Are Silicone Sealants Any Good?

Years ago, silicone caulk was a good choice for many jobs. Today, there are better options for almost every situation. So why is silicone still so popular? Here’s what one manufacturer of caulks (including silicone) told us: “Silicone is what our customers saw their fathers use. It’s what they’re familiar with.”