Out of all the construction materials, Concrete is one of the most commonly used types due to its durability and versatility. 

However, this durability does not last forever as it is still exposed to various elements which erode the concrete’s bond. Over time rain, UV rays, wind, and freeze-thaw damage weaken the concrete’s structure. 

To combat this inevitable breakdown, bonding agents are used in maintaining the integrity of the concrete. In this guide, we will highlight a few of the best bonding agents for concrete, as well as some pointers to keep in mind when choosing an option. 

Without further ado, let us begin!

Best Concrete Bonding Agents 

Here’s the list of the 11 best concrete bonding agents to help you maintain the durability and integrity of your concrete structures against the damaging effects of weather and time.

1. Loctite PL Premium Polyurethane Adhesive – Best for Versatile Bonding

Loctite provides a highly versatile Adhesive in their PL Premium line. It adheres to many different material types even under tough weather conditions. A strong bond is formed within 15-20 minutes and claims to give an adhesion three times stronger than standard adhesive.  Additionally, waterproofing and freeze preventative measures further increase durability. 

Why Did We Like It?

While using the Loctite PL Premium adhesive, the fast dry times were probably the most appreciated feature. Not having to wait for the adhesion to set in allowed for more efficient applications on multiple surfaces. 

As for the strength of the bond formed, it held together exceptionally well. In fact, it’s three times stronger than other adhesives and gives a solid bond nonetheless. 

The versatility of this premium adhesive included many common construction materials. From concrete to masonry, stone, and even metal, the adhesive had no problem in securing two surfaces together. 

Of course, painting the adhesion may not be an essential feature, but it is a good option to have. Should you so choose to paint the adhesive once dried, it can give a cleaner look to the repair or project overall. 

What Could’ve Been Better? 

Due to the application method of the adhesive, the more precise application procedures were challenging. The solution is expelled at a constant steady flow which is by no means thin. This makes surfaces that require a thin, precise application almost impossible to reach.

2. Gorilla Construction Adhesive – Best for Gap Filling

Gorilla is a well-known brand in the adhesive market. The heavy-duty construction adhesive is popularly used due to its flexibility in the materials it can be used with. Withstanding various weather conditions and accommodating its shape to changing expansion and contraction makes it stand the test of time. 

Why Did We Like It?

What made this heavy-duty adhesive from Gorilla stand out is its ability to fill in gaps of the surfaces being bonded. The solution will permeate and fill these gaps to create a stronger bond. Having those gaps filled not only kept the two surfaces bonded well but held each individual piece together better. 

As the Gorilla adhesive gives off little odor and is VOC compliant, it can be used indoors as well as outdoors. Its flexibility of adapting to changes in size due to temperature is especially helpful. Freezing or expanding due to heat is no problem; the adhesive will adjust to maintain its hold. 

A fast drying time further helps the adhesive to be used comfortably for larger projects. Once dried, the bond is sandable and paintable for a more polished look. 

What Could’ve Been Better?

There are multiple cases of the nozzle breaking or bending, causing the adhesive to leak out. Additionally, the screw-on cap has a tendency to become clogged, requiring a deeper cut to be made to access the formula. The resulting exposure can cause the glue to dry faster in the tube. 

3. PC Products 72561 – Best for Concrete Repair

Epoxy gels are incredibly strong in forming bonds, albeit they do require preparing the epoxy before applying. This epoxy gel from PC Products is a two-part epoxy that works great with concrete. With the ability to fill in the cracks in the concrete, it can give a lasting seal against water and extreme temperatures.

Why Did We Like It? 

Mixing the two epoxy parts is not as big of an issue, and the application process is relatively easy even for novices. There were 20 minutes or so of working time, which allowed the material to be adjusted before the epoxy bonded securely. After that, the adhesion was set within a few hours. 

PC Products used a high tack paste for this epoxy, which means any moisture is resisted when it is applied. Additionally, this high tack consistency makes vertical applications easier. The epoxy was able to be spread evenly to fill in cracks better.

After the epoxy is cured and dried, it becomes waterproof for extra protection throughout the concrete. It can then be sanded or painted to complete any restoration or construction project.

What Could’ve Been Better? 

Two mixing nozzles are included with the epoxy by default. These nozzles provide an easier mixing of the epoxy in perfect ratio and can then be immediately applied. However, these nozzles are for one-time use. For multiple uses, either the nozzle must be cut, or more mixing nozzles must be purchased. 

4. Gorilla Ultimate Construction Adhesive – Best for Underwater Applications

Another standout product from Gorilla is their Ultimate Construction Adhesive, with an advertised zero-second bonding time. While this claim may be difficult to believe, the fact remains that this adhesive is robust and tough. Capable of underwater application as well as an outstanding level of durability, this adhesive performs exceptionally for a range of projects.

Why Did We Like It?

Touted as the Gorilla brand’s most durable formula, expectations were high. As is the norm with Gorilla adhesives, this particular product was able to adhere to a variety of surfaces with ease. Any concerns of whether or not a specific material was compatible with this adhesive were not an issue.

Performance-wise it held its own in various degrees of moisture, expansion, and contraction due to temperature changes. Furthermore, being able to fill in the gaps of the materials is always welcome to create a more closed-off seal. 

Durability is the key feature of this adhesive. No moisture will be able to penetrate past the gap-filling adhesive once it is dried. What’s more, the adhesive is durable enough to be able to work underwater as well! Once dried, the bond is 100% waterproof.

What Could’ve Been Better?

An almost instant, zero-second dry time is one of the biggest pulls of this product. However, under different circumstances and use cases, this drying time can vary drastically. Under certain conditions, it can range from a few minutes to a few hours. While it is not an instant bond every time, the drying time does remain minimal. 

5. Loctite PL Premium Polyurethane Adhesive Tube – Best for Easy Application

Not to be confused with the previous PL Premium Polyurethane Construction Adhesive, this formula differs in its application method. This adhesive uses a tube rather than a caulking gun to be applied, with similar durability. Able to be used inside or outside on almost any construction material, it is incredibly versatile and easy to use. 

Why Did We Like It? 

Packaged in a four oz. tube, applying this adhesive is a walk in the park as compared to the caulking version. So long as the instructions are correctly followed, a strong bond can be formed on almost any surface. 

Additionally, cleanup is easy with a putty knife when the adhesive is semi-cured and has a clay-like consistency. When dried, it has a grey-tan finish, so cleanup is essential to maintain a clean look before the adhesive dries. 

When it comes to the actual strength of the adhesion, it does form a secure, permanent bond when applied correctly. Filling gaps is ideal with this adhesive, thanks to its thick viscosity. It is rated to be able to fill up gaps of up to ⅜”, which is a sizable allowance for most projects or repairs.

What Could’ve Been Better?

A downside to using an adhesive stored in a tube is the strong dependence on the nozzle of the container. In the case of this Loctite adhesive, the nozzle did tend to become clogged with dried formula and needed to be cut away. In some extreme cases, the entire tube needed to be replaced.

6. Sashco

Cracks are one of the most common repair jobs when working with concrete. The Slab sealant from Sashco is an excellent option for easily filling these cracks. The formula has been textured to best match the look of concrete to have the cleanest result possible. Additionally, it can flex to adhere to the shifting concrete for a long-lasting repair. 

Why Did We Like It?

Thanks to the numerous features the Slab sealant has, it is an ideal choice for repairing cracks in concrete. The texturing of the formula, as well as the flexibility and durability, all work together well to give a quality result. 

Needing to touch up repairs to concrete constantly can be a bothersome chore. This is not the case with the Slab sealer, as it adjusts to any shifts the concrete goes through over time due to temperature. 

Although this sealant may not fill the cracks within the concrete, it keeps the separate pieces bonded together at the surface level. Once dried, it can withstand any foot and vehicular wear and tear similar to regular concrete. 

For a more comprehensive repair, the sealer can be applied along with a backing rod for internal support. This can give the solution a firmer grip within the concrete, filling the hole beyond the surface level. 

What Could’ve Been Better?

Weather and humidity can affect how long this adhesive takes to dry and cure. In order to have complete protection from moisture, the Slab sealant requires a long curing time. This can range from a full day to a full 48 hours. This is a large window for possible contamination and can affect the durability of the sealant. 

7. Loctite Construction Adhesive

Another adhesive from Loctite is a construction adhesive with a few unique features. Where this adhesive shines is in its durable and flexible nature. Air pockets are no problem for this adhesive. Loctite has developed this adhesive to have a stronger bond than their PL Premium line, definitely one for heavy-duty uses.

Why Did We Like It?

Having peace of mind that no air pockets will bubble up once the adhesive has settled is a great feeling. No air bubbles mean the overall bond remains solid throughout the material’s recesses. It keeps the entire structure together and resists any minor movements due to temperature changes.

Applying the adhesive is relatively easy as it takes hold of the material quickly. Additionally, there is some allowance given for cold temperatures; the adhesive will not dry out even if it is exposed to colder weather. 

Furthermore, the fast grab that the adhesive has helps when working with surfaces that are difficult to clamp or are positioned awkwardly. However, there is no rush as the fast adhesion time still allows you to reposition the material before it sets and dries. 

What Could’ve Been Better?

Once this adhesive dries, it becomes incredibly solid; keep in mind there is not even room for air pockets to form. This rigidity has its drawbacks as the adhesive can potentially crack and brittle up. Possibly even breaking under extreme pressure, this adhesive may be strong, but it is not the most flexible. 

8. PC Products PC-11

A two-part epoxy from PC Products, this is an exceptional choice for any projects involving moisture or water. The high resistance to water is the standout feature of this epoxy. A tensile and cohesive structure makes this epoxy hold its shape even when applied vertically or overhead. 

Why Did We Like It?

Waterproofing in this adhesive is impressive no matter where it is used; the bond will hold strong with no problem. Even in projects that are underwater, like a pool or tank, this epoxy holds its own without allowing any moisture to pass through. 

Furthermore, the mixture has a thicker consistency that prevents dripping or sagging while it sets and hardens. There are not many adhesives that are strong enough to hold their own shape after application, so this is a truly unique feature. 

There are 35 minutes of working time which is more than enough time to set the epoxy in position. Once it begins to harden, the total time to cure is eight to 15 hours. Once set, the epoxy takes on an off-white finish. 

What Could’ve Been Better? 

Due to the thick viscosity, this epoxy has many strengths against water and holding its shape. On the other hand, this thick consistency can make it difficult to mix or work with, especially when using a large quantity. Of course, it is still entirely feasible to work with when using smaller amounts.

9. General Electric GE5020

This caulk from General Electric was designed to seal cracks in concrete and masonry with a quality bond, more of a repair or touch-up adhesive. Once thoroughly dried, it is completely waterproof and resistant to cracks and shrinking. For sealing minor cracks and recesses in concrete, this caulk is a quick and easy fix. 

Why Did We Like It?

Applying any concrete bonding agents on a rainy day can be challenging as the rain can wash away any applied adhesive. The General Electric silicone caulk is rain-proof within three hours of application, so any rain forecasts are no longer a threat. 

Besides the fast rainproofing feature of the silicone, the caulk remains permanently flexible. There is no deterioration or yellowing over time; it will shift and adapt to changes in its surroundings. As a result, the need for future touch-ups is unnecessary.

The caulk itself is easy to apply using a caulking gun. It is pushed out of the tube smoothly with a nozzle that makes precise applications easy. Once applied, it can be worked on using a putty knife to have a cleaner adhesion between the caulk and the material.

What Could’ve Been Better?

Once the caulk is applied and set, any excess caulk can be difficult to remove. Using the appropriate materials to remove the caulk can still leave a residue or cause some discoloration. As such, it is crucial to have as clean an application as possible. 

10. Liquid Nails LN-905

Outdoor stonework and concrete are most prone to breaking down due to constant exposure to different weather conditions. Liquid Nails landscape adhesive is the weather-proof solution to keep these pieces together and looking brand-new. It holds them together as one solid piece and prevents any shifting due to weather or temperature.