Build Outdoor Fireplace With Cinder Blocks

Build an Outdoor Fireplace With Cinder Blocks

An outdoor fireplace constructed from cinder blocks offers a durable and cost-effective way to enhance any outdoor living space. This project, while requiring effort and planning, is achievable for the determined DIY enthusiast. This article will guide you through the necessary steps to build your own cinder block fireplace.

Planning and Preparation: Before beginning construction, careful planning is crucial. Check local building codes and obtain any necessary permits. Choose a location for the fireplace that is a safe distance from any structures, trees, or overhanging branches. A level surface is essential for a stable structure. Consider the prevailing wind direction to minimize smoke issues. Once the location is finalized, mark the footprint of the fireplace on the ground.

Materials and Tools: Gathering the necessary materials and tools beforehand will streamline the construction process. Required materials include cinder blocks, mortar mix, concrete mix, rebar, fire bricks, a metal chimney flue, and a capstone. Tools required include a trowel, level, measuring tape, safety glasses, work gloves, a mixing tub, a shovel, and a wheelbarrow.

Foundation: A solid foundation is critical for the stability and longevity of the fireplace. Excavate the area within the marked footprint to a depth determined by local frost lines and building codes. Construct a form using plywood or similar material and pour a concrete footing reinforced with rebar. Allow the concrete to cure completely according to the manufacturer's instructions.

Base Layer: Once the foundation is cured, begin laying the first course of cinder blocks. Mix the mortar according to the package directions and apply a consistent layer to the foundation. Place the cinder blocks on the mortar, ensuring they are level and properly aligned. Check for plumb and level after each block is placed. Continue laying the first course, leaving an opening for the firebox.

Firebox Construction: Line the interior of the firebox with fire bricks. Fire bricks are designed to withstand high temperatures and are essential for the longevity of the fireplace. Use fire mortar, specifically designed for high-heat applications, to secure the fire bricks. Continue laying the cinder block walls around the firebox, ensuring the fire bricks remain flush with the interior walls.

Building the Walls: Continue stacking the cinder blocks, offsetting each course to create a strong bond, similar to bricklaying. Apply a consistent layer of mortar between each course and ensure each block is level and plumb. Periodically check the overall structure for stability and alignment.

Chimney Construction: Once the desired height of the fireplace walls is reached, begin constructing the chimney. Install the metal chimney flue and surround it with cinder blocks. Ensure the chimney flue extends above the roofline according to local building codes. Use mortar to secure the cinder blocks around the flue.

Capstone and Finishing Touches: Once the chimney is complete, install the capstone. This provides a finished look and protects the chimney from the elements. Allow the mortar to cure completely before using the fireplace. Consider adding a decorative finish such as stucco or paint to enhance the appearance of the fireplace.

Safety Considerations: Safety should be a primary concern throughout the entire construction process. Always wear appropriate safety gear, including safety glasses and gloves. Consult local building codes for specific safety requirements. Ensure proper ventilation and clearance around the fireplace. Before using the fireplace for the first time, allow adequate time for all materials to cure completely.

Maintenance: Regular maintenance is essential to ensure the longevity and safe operation of the fireplace. Inspect the chimney regularly for any cracks or damage. Clean the firebox and chimney flue periodically to remove ash and creosote buildup. Repair any damage promptly to prevent further deterioration.

Variations and Customization: The basic design can be customized to fit individual preferences and needs. Consider incorporating features such as a built-in grill, a wood storage area, or a mantel. Consult with a professional for complex designs or modifications.

Building a cinder block fireplace is a rewarding project that can enhance any outdoor living space. With careful planning, proper execution, and regular maintenance, this DIY project can provide years of enjoyment.