Sanded Caulk vs. Silicone: What’s the Difference?

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You’ve probably used caulk to fill in gaps, but what’s the difference between sanded caulk and silicone? Sanded caulk and silicone are used for different purposes. Knowing where to use each is crucial to maintaining a proper seal.

Sanded caulk is composed of a latex or acrylic base and mixed with sand. It’s ideal for large gaps but doesn’t work well with materials that flex over time. Silicone lasts longer than sanded caulk and can seal joints around flexible materials.

When you build onto an existing structure or add molding or tiles to a bathroom, it’s essential to seal the materials with caulk or silicone caulk. Caulk keeps moisture, smoke, and dirt from entering the crevices of building materials and prevents the outside air from penetrating a window or exhaust fan.

Although grout can be used on flat surfaces to bind tiles to the backer board in kitchens or bathrooms, caulk must be used to seal the joints in corners where two separate planes meet.

Sanded caulk is less flexible when it dries than silicone, which is suitable in humid areas such as the bathroom. To determine where to use sanded caulk or silicone, you must decide if the surface needs a flexible sealant if you have to paint the surface, how long the sealant should last, and the area’s environmental conditions.

What’s the Difference Between Sanded Caulk and Silicone?

Although sanded caulk and silicone are suited for different purposes, both substances act as sealants on the interior and exterior of your home. Sealants prevent air and other fine particles from penetrating the gap between two building materials.

Sanded Caulk

Compared to standard caulk, sanded caulk is partially composed of sand. The sand adds body to the sealant, allowing you to seal more significant gaps than a non-sanded sealant. The following list displays the types of sanded caulk that are available.

• Acrylic latex
• Vinyl latex
• Siliconized vinyl latex

Acrylic Latex

The most common type of caulk for home repairs and projects is acrylic latex. Unlike silicone and polyurethane sealants, acrylic latex is incredibly easy to apply. For inexperienced users, acrylic latex is ideal. It’s not too thick and glides smoothly into joints.

Sanded acrylic latex works best in large gaps wider than ⅛ inch. The sand makes the caulk denser than standard caulk, but you may need an additional filler like cardboard or a backer rod to fill large gaps.

For gaps over ½ inch wide, lay a backer rod cord into the crevice before adding the sanded caulk. The backer rod also provides stability to the caulk if the joint is wide and deep.

Acrylic latex is paintable and is used more by painters than other caulks because it’s inexpensive, paintable, and quick drying. Painters also appreciate the caulk’s simple cleaning process. After running a caulk bead, you can clean up the excess caulk by using soap and water before the sealant dries.

Sealing window frames, wood siding, molding, soffits, and other non-flexing building materials are some of the many uses of acrylic latex caulk.

Vinyl Latex

An improvement in price and quality from acrylic latex is vinyl latex. Like acrylic latex, vinyl latex is paintable and quick drying. However, vinyl latex is more durable and provides a stronger bond to separate materials than other caulks.

Vinyl latex can be used in the same areas as acrylic latex, but the vinyl caulk has superior mildew resistance. In outside areas around baseboards, windowsills, greenhouse windows, and door frames, vinyl latex is a wise choice.

Shady areas that typically attract more mold and mildew are better suited for vinyl latex.

Siliconized Sanded Vinyl Latex

Borrowing from the best properties of other types of caulk, siliconized sanded vinyl caulk is pricier than other types but is more effective in high-humidity areas such as bathrooms and kitchens.

It’s sometimes known as tile latex caulk and is ideal for bonding the deep joints where two tiles meet at the corner. Although sanded caulk is slightly more challenging to work with than non-sanded siliconized caulk, you should always use sanded caulk near tiles with sanded grout.

Non-sanded grout will not adhere to sanded caulk, and you’ll have to use siliconized non-sanded caulk for those areas. Although most siliconized caulk comes in different colors to match different tints of grout, most are non-paintable. However, you can pay more for a more advanced, paintable caulk.

Silicone Caulk

Although siliconized caulk is a suitable alternative, 100% silicone is still considered the best overall sealant for bathroom and kitchen applications. The standard silicone caught is unpaintable, but you’ll rarely need to paint where the caulk is usually applied.

Around bathtubs, sinks, tile joints, toilets, and molding are ideal locations for silicone sealants. Unlike sanded caulks silicone provides an incredibly flexible bond between two separate materials (like a metal pipe and a wooden board).

Any ninety-degree angle in your bathroom or kitchen that joins two separate materials should have beads of silicone applied as a sealant. Compared to sanded caulks, silicone is more mold and mildew-resistant and will not have to be replaced for several years.

Any material that experiences periods of expanding and contracting benefits from silicone caulk. Silicone takes much longer to dry than standard sanded caulks and is not as easy to apply as acrylic or vinyl caulks. However, specialized Silicone caulk only takes thirty minutes to dry before it is ready to paint.

Specialized silicone only needs to be used in areas with high humidity that require painting. For most kitchen and bathroom sealant tasks, 100% silicone is the sealant to use.

In high-rise buildings, outdoor silicone caulk is applied rather than standard sanded caulks because silicone flexes with the structure in high winds and will not crack.

Although more expensive than sanded caulks, silicone offers the highest protection for flexible, non-porous materials in humid environments.

What Types of Specialty Caulks Are Available?

Polyurethane Caulk

You can use one of the most durable sealants on the market for a longer-lasting bond around your kitchen sink, doors, or siding. Polyurethane caulk is a dense caulk suited for joints that hold a substantial amount of weight, such as the counter around the kitchen sink.

Like silicone caulk, polyurethane flexes when dry and is ideal for kitchen and bathroom applications. However, polyurethane caught is the only sealant safe to use near electrical lines and is perfect for insulation applications, ductwork, and electrical outputs.

Polyurethane is a thick, paintable sealant that is not easy for beginners to use, but it is longer-lasting than other caulks and is recommended for substantial DIY projects.

Butyl Rubber Caulk

Another paintable caulk that is designed for specialized tasks is butyl rubber caulk. Butyl caulk is suitable for gutters, masonry, flashing around chimneys, and exhaust fans. Butyl caulk can stay flexible under extreme conditions and is rated to seal both the inside and outside of chimneys.

Fireproof Caulk

If you need a sealant to protect materials near extreme heat, use a fireproof caulk. Although it is not technically fireproof, it is fire resistant and is ideal for sealing areas around permanent appliances that generate heat.

Fireproof caulk minimizes sound transfer between rooms (ideal for sealing recording studios) and offers the most substantial protection from fires and smoke.

Closing Remarks

Many sealants are available today, but some are designed for specific purposes and cannot be applied to every joint. Although prices vary widely from just under two dollars to over forty dollars, every type of caulk previously discussed can be purchased for under twelve dollars.

Whether you purchase the caulk online, at a paint shop, or at a home improvement center, you should never pay more than twelve dollars a tube. Specialty caulks are more expensive, but private online merchants, who charge forty-five dollars a tube for caulk, are making a hefty profit off of sealants.