Build DIY Concrete Block Outdoor Fireplace: Plans & Ideas

Picture this: you're sitting in your backyard on a crisp autumn evening, the smell of wood smoke and the crackle of a fire creating a cozy atmosphere. A concrete block outdoor fireplace is the perfect centerpiece for this scene, providing warmth, ambiance, and a focal point for your outdoor living space. But where do you start with something like this? This guide will walk you through concrete block outdoor fireplace plans, from initial design to final Brick Bond, helping you create a welcoming outdoor hearth that's both functional and timeless.

Before we dive into the details, it's important to understand the benefits of a concrete block outdoor fireplace. They're durable, weather-resistant, and provide a clean, modern aesthetic. Plus, they can be built with minimal masonry skills, making them an accessible DIY project. So, let's get started!

Designing Your Concrete Block Outdoor Fireplace

Before you grab your mortar and trowel, you'll need to plan out your fireplace's design. Consider the size, shape, and complexity of the structure, as well as your budget and skills. Here are two design pathways to consider:

Simple, Rectangular Fireplace

This straightforward design is perfect for beginners, requiring minimal cuts and complex work. It typically features a single chamber with a hearth at the bottom, and may include a simple hide for storing firewood.

Here's a simple dimension for this layout: depth - 36", width - 48", height - 72". Adjust these measurements to fit your space, but ensure the fireplace is at least 36" deep to accommodate logs safely.

Complex, Multi-Chamber Design

If you're feeling adventurous, consider a multi-chamber design. This could include a fireplace, oven, or even an outdoor kitchen. These plans require more cuts and precision, but the result is a stunning, custom piece.

When choosing a design, keep your space and needs in mind. A rectangular fireplace might suit a compact balcony, while a larger patio could accommodate a more involved design.

Building Your Concrete Block Outdoor Fireplace

Once you've finalized your design, it's time to gather materials and start building. Here's a step-by-step breakdown to help you through the process:

Preparation

First, ensure you have all necessary materials, including concrete blocks, mortar, firebrick, regex, metal fireplace grates, and any decorative accents. Also, obtain a permit if required by your local building codes, and consult with a professional if you're unsure about any aspect of the project.

Next, lay out the site for your fireplace, ensuring it's level and at least 24" away from any structures. Then, excavate the base to a depth of about 8". Fill this area with a layer of gravel for drainage and cover it with a layer of sand.

Foundation

Using full concrete blocks, build a foundation to support your fireplace. This should be at least 8" high, as it will be the base for your entire structure. Ensure the blocks are laid in a straight line and level with each other.

Apply mortar to the top of the foundation and begin laying the first course of firebricks. Firebricks can withstand high temperatures and prevent heat from damaging your concrete block structure. Follow your design plan to ensure the bricks are laid correctly.

Building the Fireplace Chambers

Using your plan as a guide, continue laying courses of firebrick, followed by a layer of concrete blocks. Maintain a level and square layout as you build upward. Remember to leave spaces for your chimney and any doors or shelves.

At the top, create a lintel using rebar to support the weight of the firebricks above. Then, finish the chimney, ensuring it's built up at least 4" above the chimney cap to allow for proper ventilation.

Finishing Touches

Now that your fireplace is built, it's time to add the final touches to make it a welcoming, stylish space.

Fireproofing and Insulation

Before finishing the inside, apply a fireproof coating to the firebrick lining. This protects the bricks from damage and prevents smoke from accumulating on their surface. Then, insulate the sides of the fireplace for safety and efficiency.

Adding Details

Now's the time to add your decorative accents. Consider adding a hearth slab for safety and aesthetics. You might also want to install a door for added safety or a custom mantel to complete the look.

Finally, apply a decorative finish to your concrete blocks. This could be a stain, a brick facing, or even plants in a surrounding bed.

As the sun sets and you light your first fire, you'll appreciate the warmth and comfort of your new concrete block outdoor fireplace. It's a space to gather, to reflect, and to enjoy the simple pleasures of life. So, grab a cozy blanket, a good book, and settle in - your outdoor hearth awaits!