How High Can You Stack Flat Top Concrete Blocks

How High Can You Stack Flat Top Concrete Blocks?

Flat top concrete blocks provide the perfect finish for any structure that makes use of Interlocking Concrete Blocks. But can flat top concrete blocks be uses alone? Can you even stack them upon each other? Or are they just used to finish a structure?

Today, we will answer the question ‘How high can you stack flat top concrete blocks?’

At PPC Concrete Products, we are here to provide solutions for your construction needs, from the person working their own part-time project, to commercial clients, and everyone in-between.

Monthly construction output had risen an estimated by an 1.6% value in June 2023, and we would like to think our accessible concrete products had a small part to play by giving our clients easy access to reliable and easy-to-use construction solutions.

Interlocking Concrete Blocks

Interlocking Concrete Blocks are an alternative to using brick and mortar in a whole host of situations. Interlocking Concrete Blocks have no need to use mortar in order to bind them. This is due to the studs and recesses at the top and bottom of the blocks that connect to ensure a lasting and secure hold.

The hold provided by Interlocking Concrete Blocks can not be undone without the use of heavy lifting equipment. In addition, concrete is naturally heavy and durable by nature, this ensures a more resilient structure, especially when considering its unique method of obtaining a secure connection.

Here is a list of some of the uses that Interlocking Concrete Blocks can facilitate.

  • Material Storage bays
  • Blast walls
  • Salt stores
  • Crash protection
  • Push walls
  • Security barriers
  • Segregation bays, i.e. recycling centres
  • Retaining walls
  • Industrial buildings
  • Fire breaks
  • Counterweights
  • Roadblocks

Is using bricks better than Interlocking Concrete Blocks?

Interlocking Concrete Blocks explained

Depending on the structure, bricks may be the suitable alternative, but generally, in terms of ease of use, speed, durability, and sometimes cost, Interlocking Concrete Blocks are the winner.

Interlocking Concrete Blocks are typically larger than bricks, so they cover a larger area whilst using less than you would with bricks. This also can increase the speed of the build at hand.

Bricks require a certain amount of mortar between each brick at all sides, except from the inward and outward faces. The mortar must also have the right consistency and application in order to be effective, and must not be tampered with until it is fully dry. What this basically means, is a lot can go wrong with bricklaying.

Interlocking Concrete Blocks only require a specific alignment before being placed and establishing a connection through the studs of the block beneath, and the recesses of the block being placed upon it.

Cost wise, Interlocking Concrete Blocks may also end up being the cheaper option, simply because you need less blocks than you need bricks for the same structure. Additionally, you won’t have to pay for extra resources such as mortar.

Is there a benefit to using mortar?

Although it can raise the overall cost of your build, using mortar, or lime mortar can be helpful in construction. That being said, the following information does not apply to Interlocking Concrete Blocks, as they do not need mortar to have a permanent and secure connection.

Mortar binds two bricks, blocks or stones together. This binding mostly prevents moisture or anything else from entering the structure between the bricks/blocks/stones. Over time, mortar will either wear away or crumble, or become softer, depending on the kind of mortar you use. This would mean maintenance has to be undertaken to keep the structures’ integrity.

What is a flat top concrete block?

Can I repair concrete blocks that have been crumbled?

The flat top concrete block, sometimes known as a flat top interlocking concrete block, or a flat top block, is a block that is characterised by having the mechanisms of an Interlocking Concrete Block. It is a block that is characterised by having one of the mechanisms of an Interlocking Concrete Block, but without the studs at the top.

As a result, the flat top block is exclusively used as the finishing blocks of any structure that requires the use of Interlocking Concrete Blocks.

Flat top blocks are made in such a way to prevent possible trip hazards, for structures such as a small retaining wall. Additionally, it can help the constructor to know which block needs to be on the top.

How high can you stack flat top concrete blocks?

How many concrete blocks do I need?

Our Flat top concrete blocks can not be stacked upon each other, as there is no secure connection at the top of these blocks. However,  our interlocking concrete blocks have the potential to have 5 blocks stacked upon each other. This means that the fifth topmost can be a flat top concrete block.

When it comes to the height, Our standard-sized blocks are 60 cm in height, with 5 stacked together this would equate to 300 cm, which is exactly 9 feet (2.74 m) & 10.11 inches (ca. 26 cm) high. This means that a flat top concrete block can be placed at a maximum of 9 feet (2.74 m) high.

What happens if I stack flat top blocks?

It is not recommended to stack flat top blocks upon each other. There is no secure connection mechanism available at the top of the block in order to attach to the block that is placed upon it.

As a result of this insecure attachment, your structure has a much greater risk of toppling, whether this be through manipulation or as a result of a heavy impact. This is dangerous to do, and has the potential to cause death or serious injury, depending on the height that the flat top blocks are stacked to.

Can I secure flat top blocks with mortar?

Stacking flat top blocks upon each other is not recommended, even if you decide to use mortar to bind them together. Mortar will definitely result in a more secure bond than if you decided to stack the flat top blocks without anything.

However, you could be spending more money than you actually need to by deciding to stack flat top blocks and securing them with mortar. The best option is to use Interlocking Concrete Blocks, and finishing them with a flat top block.

How much do Interlocking Concrete Blocks weigh?

In regard to the weight of the blocks, it will vary from size to size, and from the concrete being used. But as an example, 1800 × 600 × 600 concrete block can weigh 1560 kg, this can fluctuate as different types of concrete have different levels of density.

When it comes to flat top blocks, they may have a nominal difference in weight due to the difference in shape. However, this difference is not enough to compromise the effectiveness of the block itself.

The weight of these blocks ensures a rigidity that can not be tampered with unless the use of heavy lifting equipment is employed.

Buy flat top blocks today

As an established supplier all over the UK, PPC Concrete Products is always happy to help, which is why we encourage you to get in touch with any questions you may have or have a look at our FAQ.

In this blog, we hope to have provided key information for the question ‘How high can you stack flat top concrete blocks?’ Whilst also providing additional information, including construction solutions that we offer.

Take a read of our case studies to truly understand how we have provided solutions for business in the past with the use of our Interlocking Concrete Blocks, and ultimately, how we can help you today.

Read our blog page for more insights into our passion, construction.


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Tel: 01706 655245


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