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Do I Need To Glue My Retaining Wall Blocks

Do you intend to construct a retaining wall? If so, you may have received mixed answers regarding the use of adhesive between the blocks. You might or might not need glue between the layers of your retaining wall, depending on the type of blocks you’re using.

You’ll quickly see that interlocking blocks don’t require adhesive as they won’t serve any other purpose. If you construct a wall with cinder blocks, filling the holes with cement, you won’t need glue.

Moving on, besides these or other similar techniques, you will be advised to use masonry adhesive for added strength. Besides the walls, you need to consider the retaining wall cap, as these won’t have any additional fixing method.

In our guide, you can learn more about which concrete glue is best for retaining wall blocks and your wall cap. By the end, even if it’s your first retaining wall, you’ll be able to pick the best landscaping adhesive and see how to apply your retaining wall glue for maximum strength. (Read Growing Plants In Sphagnum Moss)

Best Glue for Retaining Wall Blocks

Should I Glue Retaining Wall Blocks?

When building retaining walls, glue is not always necessary, but it will typically help your wall last longer. There are numerous retaining wall blocks available for use in retaining walls.

You can find some interlocking blocks that allow you to build walls up to 50 feet high without masonry adhesives. Traditional retaining wall blocks are not as easy to install as interlocking concrete blocks, making your wall-building job more manageable.

Pros and Cons of Retaining Wall Adhesive

When you apply glue to retaining walls, it offers many advantages.


  • First, since you don’t need to mix glue, it is simpler to use than mortar.
  • Construction adhesive dries much more quickly than mortar, taking only a few hours instead of several days.
  • Glue is less messy and requires less cleanup. However, you run the risk of your wall becoming unstable and moving out of position if you decide to forego using glue and mortar altogether.


  • The drawback is that sagging walls shouldn’t be adhered to with construction adhesives. This is because these are not entirely vertical walls.
  • The glue will run off the surface of the blocks as it is applied.
  • Additionally, construction adhesives aren’t the best option if you intend to construct a retaining wall taller than three feet tall.

For more information, refer to the manufacturer’s instructions.

What Is The Best Adhesive For My Retaining Wall?

Landscape block adhesive products don’t all live up to their claims. That’s why we researched and found the strongest glues on the market. Liquid Nails is a well-known brand, yet it may not maintain its strength on concrete like other materials.

No matter what masonry adhesives you choose, applying these to your concrete is easier when using caulking guns. Here’s a quick overview of the best adhesive options you can find to stick your wall blocks together. (Read our Digging A Trench Guide)

Loctite Premium Construction Adhesive

1. Loctite Premium Construction Adhesive

Both indoor and outdoor use of Loctite Premium is acceptable and repositionable, allowing for errors.

It is eight times stronger than other brands, as claimed by the manufacturers. It offers a solid initial hold, and the finished product can be painted over.

2. Loctite PL 500 Landscape Block and Paver VOC Construction Adhesive

Loctite also produces a landscaping adhesive that is tailor-made for blocks and pavers.

You can apply it to wet or dry surfaces, and it still delivers excellent bonding of concrete and stone.

It is only intended for outdoor use and withstands temperatures between 0°F and 100°F, and you can apply it to frozen surfaces if your retaining wall blocks get cold overnight.

3. Gorilla Glue Max

Of all the Gorilla Glue products, Max Strength Construction Adhesive offers the strongest bond, and you’ll find the waterproof, non-foaming formula dries clear.

Even underwater applications are possible and will function in all weather, suitable for indoor and outdoor use.

4. 3M Marine 5200

3M Marine 5200 is an excellent adhesive, yet it will begin drying in 12 hours and can take up to 5 days to fully cure. One downside of the slow drying time is it could affect the installation of your second row of blocks.

With a liquid between your retaining wall blocks, it could be possible to knock them or slide out of position.

You can apply it at various temperatures, yet it dries black, so if your concrete blocks are light, it could leave a mess. (Learn How To Get Rid Of Pine Needles)

5. F-26 High-Strength Gel

F-26 provides a solid bond that is long-lasting and water-resistant. Use both inside and outside. It has a 15–40 second open time and cures in 24 hours.

However, it will strengthen over time, particularly in the first week after application.

F-26 can be used in temperatures ranging from 0°F to 1200°F and is suitable for use on wet or frozen surfaces. It is also not affected by humidity, so it is more than ideal for outdoor settings.

How Do You Glue Retaining Wall Stones?

  1. It is crucial to remember that the first row of stones in a retaining wall won’t need adhesive. Instead, you will press those snugly into the bottom layer of gravel, sand, or other material you use as a base.
  2. You should apply a thin layer of glue over each block individually, starting with the second row of bricks, stones, or blocks.
  3. Never cross the bottom stone with the top block. Rather, firmly press it on top of the bottom block.

Cinder blocks and gorilla glue: Will they stick?

Gorilla Glue will work on cinder blocks, but you shouldn’t apply the original recipe. Try Gorilla Glue Construction Adhesive as an alternative. Build your retaining wall using Gorilla Construction Adhesive as well. The Gorilla family of products’ Gorilla Max Strength Construction Adhesive provides the strongest bond and dries clear for a beautiful finish.

In addition, Gorilla Construction Adhesive is waterproof and keeps a solid bond in all weather conditions while submerged in water.

The repositionable qualities make it easy to fix mistakes with an extended opening time of 30 minutes and a cure time of 24 hours. However, don’t forget to purchase a caulking gun for easy application.

How To Secure a Retaining Wall Block Cap?

Level your concrete retaining wall block before capping it. Uneven stones or blocks must be cut to the same size, leaving approximately three inches of overhang.

Once the concrete cap fits nicely, apply adhesive and press the cap firmly onto the wall. Instead of capping cinder blocks after filling them with cement, apply a layer of mortar. If you want an overhang, buy caps.

Planning Your Block Retaining Wall

There are several retaining wall systems to consider when building your wall. You can use gravity-held blocks with pins for easy assembly or blocks with an interlocking lip.

The lip makes the block lockable, making retaining wall ideas easier. The interlocking retaining wall block can be stacked to build walls 24 to 36 inches high, depending on the block size; just ensure you follow the block manufacturer’s instructions for wall height limits.


  1. If the retaining wall is against the house, keep soil and mulch and downspouts pointed away from the siding and your concrete block.
  2. How you mark the area depends on your retaining wall design. Using a rope or hose, outline a free-form layout.
  3. Then outline with a shovel—Mark straight lines with stakes, string, and paint.
  4. Mark curved corners by tying a string to a central stake and spray-painting the curves.
  5. Divide the wall’s length by the block’s length to determine how many per row.
  6. Divide the ideal wall height by the block height; the first row will be half-buried.

Loctite PL 500 Landscape adhesive


What is the best landscape block adhesive?

The block’s lip creates a locking flange, making retaining wall ideas easier. If the retaining wall is against the house, keep soil and mulch below the siding. How you mark the area depends on your retaining wall design.

  • Retaining wall caps: Apply 1/4″ to 3/8″ bead 2″ from the block edge, and to ensure adhesive contact, press firmly.
  • Retaining wall blocks: Apply two 1/4″ beads of adhesive front and back on each block. To ensure adhesive contact, press firmly.

How do you separate glued landscape blocks?

Holding the chisel at a shallow angle—almost flat—and tapping it with the hammer will help you scrape the masonry adhesive off the concrete wall and capstone.

Apply paint thinner and mineral spirits to the stones to remove any remaining adhesive bits. Then, use a chisel to scrape the adhesive off. (Read Cheapest Way To Cover Dirt In Backyard)

How do you use Loctite PL 500 Landscape adhesive?

To bond, a surface, apply a continuous zigzag bead to one surface of your concrete blocks. Then, apply the adhesive quickly enough for the concrete blocks to be placed and secured in less than 15 minutes.

Every project might require support until the landscape block and the adhesive has dried.

What are the strongest Liquid Nails?

The Liquid Nails Fuze*It Max offers exceptional grab and long-term strength; the interior and exterior all-purpose construction adhesive creates the strongest bond from beginning to end.

How long should you let liquid nails dry?

Drying Time Liquid Nails advise bracing or clamping the adhered surfaces for 24 hours, and it may take an additional week for the product to fully cure.

Do I Need To Glue My Retaining Wall Blocks