The sequential steps to building an outdoor fireplace are constructing fireplace footings, making the base and firebox, constructing the throat and flue and finishing off with stonework. Although simple to perform, it is a good idea to get professional advice before and during fireplace construction.
Choose the location with care, as it is easy for a free-standing fireplace to tip over on uneven ground. Some experts recommend putting rebar in to secure the foundation. Check building codes for concrete depth regulations before laying the foundation, and other local codes should be followed throughout the process. Let the concrete foundation sit for at least 24 hours before the next steps are taken.
The base provides a more even surface for the rest of the structure. Some builders use 4-inch solid blocks, upon which they use firebricks and refractory cement for the firebox. Once the firebox is finished, build the throat. Use steel angle iron and additional masonry to help support the material while building towards the throat in the center. The flue block goes in the throat after the flue liner is set on mortar, and can be adjusted in height as desired.
The final step is the stonework, which offers a greater degree of freedom to design according to taste.