How to Build an Outdoor Fireplace in 10 Easy Steps

Category: Article     Tags: Fireplace, How-To, Tips

Bremley TV-Deluxe-Estate Fireplace kit

Prep Your Location Before You Build Your Outdoor Fireplace

Are you ready to build your outdoor fireplace? Before you start laying blocks, make sure you’ve covered all the essential groundwork in Part 1.


In Part 1, we explored the crucial pre-build considerations that will make or break your project. From understanding local building codes and planning your patio layout to choosing and setting a solid foundation, this guide laid the foundation (quite literally) for a successful build. Below is a quick summary to get you up to speed, but be sure to check out the full article for more detailed insights, examples, and expert tips.

Please Follow Part 1 – Here is an overview of what planning and preparation should be completed before you begin laying stones.

A. Check Your Local Building Codes

Before you break ground, familiarize yourself with local, state, and HOA regulations around outdoor fireplaces. These codes can affect the placement, size, and even the type of fireplace you can build. While most regulations are straightforward, some may have unique or unexpected requirements. Creativity in working with your code official often provides a path forward, so don’t be discouraged if you hit a roadblock.

B. Plan Your Patio Layout

A well-designed patio layout is key to a functional and enjoyable outdoor space. Take your time sketching out different configurations, walking through the space to understand traffic flow, and considering how furniture, entrances, and safety exits fit into your design. Remember, any changes made after the build are costly, so make sure you get it right the first time.

C. Plan a Stable Foundation for Your Fireplace Kit

The foundation is the backbone of your fireplace. Depending on your soil, local codes, and preferences, you can choose between a concrete pier foundation or a compacted gravel base. A stable, well-built foundation ensures that your fireplace stands strong for years. Our how-to video and downloadable specs will walk you through preparing the best foundation for your outdoor fireplace.

D. Build Your Outdoor Fireplace Base

The final part of Part 1 covers the initial build of your fireplace base, focusing on laying the groundwork. Proper excavation is key; too wet or too dry soil can make things more difficult than they need to be. A stable gravel base or concrete pad with rebar provides a level surface for the fireplace structure, allowing you to move smoothly into the next steps.

Barrington Kit Deluxe Estate in Cottage Buff DIY stone outdoor fireplace kit with double wood storage box and wing walls with columns

How to Build an Outdoor Fireplace- Part 1: The Foundation

Before you lay the first block, make sure you’ve covered the essentials. From understanding building codes to planning your patio layout and preparing a solid foundation, this guide helps you avoid costly mistakes and set up your outdoor fireplace project for success.

Gather Tools & Instructions for Your DIY Outdoor Fireplace Project

Let’s learn how to build an outdoor fireplace! You finished your foundation, and it is perfect. Now you are ready for the fun part. The build will go fast. There is no need to get in a rush. Take your time and be deliberate. Remember, take a break when needed, and stay hydrated. This fireplace will last for years. Be sure to get it right now, as you won’t be able to fix it later.

Jake standing in front of a deluxe estate outdoor fireplace for scale.

These articles offer insights you won’t find anywhere else. They are based on my videos, which offer insights and tips you won’t find in these articles. Be sure to watch and reference my instructional video series. By watching my videos and reading these articles, you will be ready to build your personal outdoor fireplace to help create your dream backyard paradise. If you still have questions, be sure to contact us.

Tools Needed to Build Your Outdoor Fireplace

Having the right tools on hand will make your fireplace build smoother and more efficient. Here’s a list of the essentials you’ll need for the job:

Dead Blow Hammer

Used for precise adjustments and setting blocks without damaging the surface.

Caulk Gun

For applying adhesive or sealants to secure your materials.

4-Foot Level & 2-Foot Level

The longer level will help ensure larger sections are aligned properly, while the smaller one is great for tighter spaces and adjustments.

Square (Drywall Square Works Best)

To make sure your angles are precise and that your blocks are laid out correctly.

Ladders (6 Ft Minimum)

Ladders are essential for reaching higher parts of your fireplace safely as you build upward.

PPE- Gloves, for sure- maybe more

All the pieces are pre-cut for you. You simply stack and glue your blocks. Wear gloves to keep the adhesive off and prevent the blocks from abrading your hands. If you need to grind any blocks, you will need to wear safety goggles, hearing protection, and a face mask/respirator to keep from breathing dust and particulates.

Watch the Step-by-Step Video Guide Build Your DIY Outdoor Fireplace Kit

Build your fireplace in a weekend youtube video

Learn from the Pros – Check Out Our How-To Videos on YouTube

You will learn what to expect when building this project yourself. All of Jake’s kits are perfect for installers or DIYers. You don’t need any special skills or tools. All the pieces you need are included in your kit. There is no cutting or mortaring the blocks. You simply stack and glue the block together.

Your outdoor living kit comes with easy-to-follow step-by-step instructions
Downloadable PDF Plans

This Article is an In-Depth explanation of our Downloadable PDF Instructions. Download them here.

Dowload the appropriate PDF plans for your fireplace HERE. Follow along to gain more valuable insight into your backyard DIY fireplace project.

Construction Tips to Know Before Building Your Outdoor Fireplace

There is no mortar needed to build this kit. You will glue courses of blocks together to build your kit. After laying a course of block, sweep it clean. Then, you can apply adhesive on top of the blocks. Place the next layer on top of the block to adhere them together. Next, brush off any loose debris before setting a stone. To be clear, you do not need to glue the sides of the block together unless stated otherwise. Apply the glue sparingly. Note it is best if you feel the blocks scrape together when stacked. You don’t want the blocks to slide and float on a thick pad of adhesive. A double 1/4″ bead is usually ideal. Glue has a slight thickness. Don’t forget, you can use dollops or glue one side to adjust your blocks less than 1/8″.

This kit mainly consists of layers (courses) of rectangles built from your blocks. Be sure to keep the blocks in straight runs when constructing this kit. Doing this will ensure that your blocks end up at the proper length. As you can see below, if the blocks aren’t in line, the length of the run will change. Keep your courses straight, square, level, and plumb. You can only build a wall to one side. For best results, align the blocks to the outer surface of your kit. Any variance in the material will only show on the inside.

Follow these Instructions for laying the blocks to build your outdoor fireplace

1. Lay the All-Important Base Courses

The importance of your first course cannot be overstated. Take the time to make sure it is perfectly square and level. Any imperfections here will continue as you build your kit. Begin from the center out and use your level as a straight edge to keep your blocks aligned.

Level Your Base Course

Using a level, ensure that your base course is square and evenly laid.

2. Prepare To Build the Fireplace, Hearth, and Firebox

Once the base courses are level and square, it’s time to add the hearth and complete the firebox. Typically, you only glue the top faces of the blocks. For the hearth, which will bear more weight, consider adhering the ends and sides of the hearth blocks as well. A single bead of glue down the center spreads the load effectively.

PRO TIP: Allow the adhesive to cure before stepping on the hearth, or glue it on at the end of the build to avoid any damage during the process.

In our Video, Jake shows you how to lay the hearth of your fireplace kit

3. Install the Hearth

The hearth is a key component, as it may be knelt, sat, or stepped on. Glue the ends and sides of the hearth blocks for added stability. A single bead down the center will evenly distribute the load.

PRO TIP: Ensure the adhesive cures before continuing to prevent shifting or tipping.

4. Install the Firebox

The firebox is the heart of your fireplace, where combustion happens, and the draft is created. The solid masonry absorbs and radiates heat for hours. Thankfully, the firebox is pre-designed to draft efficiently, so all you need to do is build a box while keeping it plumb and square.

Key Tips for Building the Firebox

  • Keep your build plumb.
  • Start each course from the back corners.
  • Use your level as a straight edge.
  • Align multiple courses to avoid twisting.

Line the Firebox with Firebrick

Though not required by code, firebricks add durability and extra heat retention. Use firebrick-specific adhesive for proper placement. Follow the provided instructions to align your firebricks, starting from the front and working toward the back, leaving a slight air gap.

Time to start lining your firebox with firebrick

Start the Firebrick at the Front

Leave an Air Gap in the Corner

Lay the pre-cut firebrick to complete your pattern

Place the Cut Firebricks

5. Install the Angle Iron Across Your Firebox Opening

The angle iron is a lintel to support the masonry above the firebox opening. Ensure that the longer side of the angle points upward and is flush with the surrounding blocks. Glue the bottom and sides of the lintel block for extra support. If needed, use shims or mortar for leveling.

Install Firebrick Around the Lintel

Use firebricks around the angle iron to complete the firebox opening.

There are special lintel block to support your fireplaces lintel. Find them in your kit.

Place the Lintel Support Blocks

Placing firebrick arount the angle iron of your firebox

Firebrick Around the Lintel Detail

Keep your courses level!

Be Sure the Firebox is Level. Use shims or a grinder if needed.

Laying the lintel on your outdoor fireplace kit

Be sure the lintel stays flush with the surrounding blocks. Use mortar or shims if needed.

6. Build the Throat of Your Outdoor Fireplace

The throat is a few courses above the firebox and leads into the smoke chamber. Before laying blocks across the lintel, stack support blocks in the firebox opening to prevent tipping. Continue stacking until it’s time to start racking for the smoke chamber.

Completing the fireplace firebox

PRO TIP: Take a break here if needed and ensure everything is level before moving on.

7. Racking Blocks – Build the Smoke Chamber

The smoke chamber narrows the rising column of hot air, creating the draft for your fireplace. Rack each course back evenly on both sides, using your fingers to gauge setbacks and maintain an even build.

Racking the throat of your fireplace kit

The Smoke Chamber Racks Back- Use your finger as a practical guide.

Fireplace-Build-Hearth

Installing the Mantle of your outdoor fireplace takes special consideration- read your instructions.

Fireplace kit build- keep your blocks straight and flush

Keep the Racked Courses Straight

How-to build a fireplace- Starting the chimney

Finish the Smoke Chamber

Be sure to rack evenly in each successive course on both sides. Use the “finger trick” to ensure an even setback. Also, you won’t have the back corner of the firebox to work off of as a reference. Be sure to take your time and keep the smoke chamber square, level, and plumb.

8. Build the Fireplace Chimney

Now that you’ve reached the chimney, the four straight sides will make keeping plumb easier than the smoke chamber. If you’re installing wood boxes, do so before building the chimney, as they can provide a platform to stand on. Alternatively, use a six-foot ladder to reach the higher courses.

Consider extending the chimney height for a better draft if you encounter downdrafts or strange air currents.

Keep the chimney of your fireplace kit plumb

Build Your Chimney Plumb

Straightening the chimney of an outdoor fireplace kit

Keep your Chimney Flush and Straight

9. Install the Chimney Trim Stones

The trim stones are the finishing touch on your chimney. Carefully place the eight square trim pieces to ensure they are straight and aligned. Be mindful of glue placement to avoid visible adhesive from below.

PRO TIP: Place the best-looking sides of the trim stones facing down, as they will be viewed from below.

Building the chimney of an outdoor fireplace kit
Stainless Steel Spark Arrestor

10. Install the Spark Arrestor

Unlike heavier concrete caps, the lightweight stainless steel spark arrestor is easy to install and provides safety by preventing floating embers from escaping. It is one of the final steps to complete your outdoor fireplace build.

Congratulations on completing your outdoor fireplace project! You just built a Fireplace!

You have just finished your Outdoor fireplace kit! Be sure to add a fire grate to burn your logs. We do not include fireplace grates due to their many designs and users’ personal preferences. You can buy self-feeding fire grates, fancy ones, grates that maximize popping, grates for sappy wood, etc. Learn about your options and choose the one that matches your needs and design criteria. You can always convert it to gas logs, too.

Barrington Classis DIY Outdoor Fireplace Kit shown in Cottage Buff Stone color
Barrington Classis DIY Outdoor Fireplace Kit shown in Cottage Buff Stone color

Design & Build Your Outdoor Kitchen with Confidence

Ready to design your outdoor living space? Whether you’re planning a DIY build or professional installation, explore our layout guides, how-to videos, and design tips to make your outdoor living dreams a reality. With Cornerstone’s top-rated Fireplaces and versatile Unity Series Outdoor Kitchen System, building your custom backyard oasis is not just a project—it’s an experience.

Start with these informative posts:

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