Embarking on a DIY concrete deck project? You’ve likely come across concrete deck blocks, a versatile and robust solution for creating durable, long-lasting decks. But how do you use these blocks effectively, especially when it comes to supporting your posts? Let’s delve into the world of concrete deck blocks and explore how to use them for your posts, with a focus on YouTube tutorials for visual guidance.
Before we dive in, remember that safety is paramount when working with concrete. Always wear appropriate Personal Protective Equipment (PPE), including gloves, safety glasses, and sturdy boots. Now, let’s get started!

Understanding Concrete Deck Blocks
Concrete deck blocks, also known as concrete patio blocks or paving slabs, are manufactured in various shapes and sizes. They are designed to interlock, creating a stable, level surface for your deck. Understanding their design and purpose is crucial before using them for your posts.
Most concrete deck blocks have a lip or lip-and-tongue design on their edges, allowing them to fit together securely. This interlocking system helps distribute weight evenly, preventing the blocks from shifting or moving over time.
Choosing the Right Blocks for Your Posts
When selecting concrete deck blocks for your posts, consider the load they’ll bear. For standard deck posts, 2″ or 3″ thick blocks should suffice. However, if your posts will support heavy structures or equipment, opt for thicker blocks, such as 4″ or 6″.
Also, ensure the blocks have a flat, level surface. Some blocks may have a textured or beveled top, which isn’t ideal for supporting posts evenly.

Preparing Your Site
Before laying your concrete deck blocks, prepare your site by clearing any debris and leveling the ground. A well-prepared site ensures your blocks sit evenly, promoting stability and longevity.
You can use a string line and level to mark out your deck’s perimeter and ensure it’s square. This step is crucial for maintaining a straight, level surface throughout your project.
Laying Concrete Deck Blocks for Posts
Now that you’ve chosen the right blocks and prepared your site, it’s time to lay them for your posts. This process involves creating a stable base and ensuring your blocks are level and square.

For visual guidance, check out YouTube tutorials like “How to Build a Concrete Deck” by This Old House or “Concrete Patio Blocks Installation” by Home Repair Tutor. These videos provide step-by-step instructions and visual demonstrations.
Creating a Stable Base
Start by laying a bed of sand or gravel, ensuring it’s level and well-compacted. This base provides a stable foundation for your concrete deck blocks, preventing them from settling or shifting over time.
You can use a level to ensure your base is even, and a trowel to smooth out any uneven areas. Once your base is level, you’re ready to begin laying your blocks.
Laying Blocks for Posts
Begin at one corner of your deck, laying your first block along the string line. Use a rubber mallet to tap the block into place, ensuring it’s level and aligned with the string line. Continue laying blocks in this manner, working your way out from the corner.

When you reach the location of your post, cut your block to size using a wet saw or masonry blade. Ensure the cut block is level and stable, providing a solid foundation for your post.
Supporting Your Posts
Once your blocks are laid, it’s time to install your posts. You can use post anchors or post bases to secure your posts to the blocks. These devices help distribute the weight of your post evenly, preventing the blocks from cracking or shifting.
Drill holes in your blocks to accommodate the post anchors or bases. Insert the anchors or bases into the holes, then secure your posts using appropriate fasteners. Ensure your posts are plumb (vertical) and level before securing them in place.
Finishing Touches
With your posts securely in place, you can continue laying your concrete deck blocks, working your way around your deck. Ensure each block is level and aligned with the previous one, maintaining a straight, even surface.

Once your deck is complete, consider applying a sealant to protect your blocks from moisture and stains. This step helps extend the lifespan of your deck, ensuring it remains durable and attractive for years to come.
Congratulations! You’ve now successfully used concrete deck blocks for your posts. By following these steps and seeking guidance from YouTube tutorials, you’ve created a durable, long-lasting deck that you can enjoy for years to come. Happy building!




















