DIY Outdoor Fireplace Guide

An outdoor fireplace can be a great addition to your outdoor living space, providing a cozy spot for relaxation and entertainment. Building your own outdoor fireplace can be a fun and rewarding DIY project, but it requires careful planning and attention to detail.

Step-by-Step Guide to Build an Outdoor Fireplace

Planning and Preparation

It all starts here. When planning your fireplace design and layout, take into account available space and the style of your house and backyard.

Specific considerations include:

• Local codes and regulations: Check local codes, HOA rules, and other regulations regarding fireplace construction.
• Building materials: Decide what materials you want to make your fireplace out of. Stone, stucco, and concrete are popular options.
• Tools: Make sure you have the necessary tools and expertise to complete the project safely and efficiently.
• Type of fireplace: Do you want a wood-burning, electric, or gas fireplace? Your decision will impact construction as well as the materials and permits you need. (For the purposes of this article, we will focus on basic wood-burning fireplaces made with concrete blocks and fire bricks.)

Gathering the Materials

Here is what you'll need.

Tools:

• Trowel
• Shovel
• Circular saw
• Measuring tape
• Masonry hammer
• Level
• Tamper
• Caulk and caulk gun
• Drill with masonry drill bit

Foundation materials:

• Concrete blocks/cinder blocks (CMUs)
• Mortar
• Gravel

Firebox materials:

• Fire bricks
• Grate or insert
• Heatproof screed or other adhesive
• Pre-fabricated lintel
• Mortar

Smoke chamber materials:

• CMUs
• Fire bricks
• Mortar

Chimney materials:

• CMUs
• Fire bricks
• Pre-made chimney cap
• Masonry screws
• Mortar

Miscellaneous materials:

• Permits

Laying the Foundation

A solid foundation is essential for a successful build; take your time here, or your entire structure will be compromised.

1. Select a space at least ten feet away from any other structure. Mark the outline with a shovel.
2. Remove any debris from the area.
3. Use a shovel, level, and tamper to create a flat space that is big enough to support your fireplace. It should be at least 4 inches deep.
4. Once leveled, create a foundation by adding a layer of gravel at least 4 inches deep.
5. Compact the gravel and ensure it is level.
6. Lay the concrete blocks over the gravel and ensure they are level.
7. Use mortar to adhere the blocks together.
8. Repeat Steps 6 and 7 until your foundation reaches your desired height.
9. Let everything cure.

Constructing the Firebox

A firebox is the very center of your outdoor fireplace. Plan carefully and use the right heat-resistant materials for a long-lasting fireplace build.

1. After laying your foundation, begin building the firebox using cinder blocks for the exterior; the interior will be lined with fire bricks. As the name implies, it should roughly be the shape of a box.
2. Use mortar to adhere all blocks and bricks.
3. Level each layer before moving onto the next one.
4. When reaching the top of your firebox, leave an opening. This space will be where you add your lintel for added structural support. You can purchase heat-resistant lintels at big box stores like Lowe's and Home Depot.
5. Add mortar to the place you will add the lintel, then add the lintel on top of the mortar.
6. Add the final layers to your firebox.
7. Let all materials fully cure and settle.

Creating the Smoke Chamber

Creating the smoke chamber is an important component of your outdoor fireplace construction plans, as it helps to direct smoke and gases away from the firebox. The exterior should be CMUs and the interior fire bricks.

1. At the top of your firebox, put down a layer of mortar.
2. Begin laying the materials for your smoke chamber. Along the sides, lay bricks 2 inches in. Along the front, lay bricks 4 inches in.
3. Ensure each layer is level before moving to the next one and laying more mortar and bricks.
4. Add the next layer. The sides should be 2 inches in from the previous layer while the front is plumb with the previous layer.
5. Continue until your smoke chamber is the desired size.
6. Wait until everything fully cures before moving on to the next step.

Adding the Chimney

A chimney will help direct smoke and other harmful gasses away from your completed fireplace and living area. Don't neglect its construction and ensure its height meets all local building codes.

1. Put down a layer of mortar.
2. Add the fire bricks and CMUs in a level, plumb layer.
3. Repeat Steps 2 and 3 until reaching the desired height.
4. Let everything cure.
5. Next, add the chimney cap. To do so, grab your pre-made chimney cap and align it to where you want it on the top of your chimney. Holding the cap in place, use your drill to add pilot holes to the chimney, ensuring they are aligned with the pre-made holes in the cap.
6. Use your masonry screws to attach the cap to the chimney.
7. Add your heat-resistant caulk to seal the edges along the cap's bottom.

Other Outdoor Fireplace Ideas

Constructing a DIY outdoor fireplace can be a rewarding DIY home improvement project. It might be difficult for those without prior experience, however.

More beginner-friendly alternatives for homeowners include:

• Fire pits. Fire pits are vastly easier to install and maintain than fireplaces. If this is your first DIY project, consider creating a fire pit instead of a full-blown fireplace.
• DIY outdoor fireplace kits. If you are set on making your own fireplace, consider using a kit instead of building everything yourself from the ground up.
• Professional services. For fireplaces that are durable, functional, safe, and compliant with all local codes, consider hiring professional fireplace builders.