Brick fire pit. How to organize a garden hearth at home and in the country? Option #1

A fire pit in a country house is rightfully considered one of the most important accessories in a yard. Most owners of land plots simply cannot imagine life without evening gatherings by an open fire, when all business is over, peace and grace reign on the street. Carefully and thoughtfully designed open hearth is a practical multifunctional structure that can last for decades. Today, when making a hearth in the garden, people pursue not only utilitarian goals. The country plot is used for relaxation from the city noise and bustle. In such cases, the dacha hearth becomes a spectacular element landscape design. Applying modern technologies And non-standard solutions, fireplaces for cauldrons, barbecues and skewers, can be made on the lawn, veranda and even in closed gazebo. Let's look at how to make a fireplace in your country house with your own hands so that it is beautiful and safe.

When planning construction, it should be remembered that an open fire poses a serious fire hazard. The fire may spread throughout the area. Based on this, the choice of location and design of a fire pit on the street must be approached very responsibly.

Barbecues, fireplaces, hearths and other structures whose operation involves open flames must be built at a distance of at least 10 m from wooden buildings. Such structures include barns, fences, livestock pens and residential buildings.
The fire pit at the dacha should be built on a hill. To protect yard fires from storm and melt water, you should consider the arrangement drainage system. Drainage is also needed to keep the area of land that surrounds the open hearth in the country dry.
The most practical and convenient to use is considered to be a round hearth. It burns the wood completely and evenly, creating a constant, steady heat. The absence of corners prevents the accumulation of dirt and the development of mold.
When starting to build a fireplace or barbecue with your own hands, you need to make sure that there are no communications under or above these structures. Not worth building garden hearth Near big trees. Their roots can destroy the masonry, and the foliage can catch fire under the influence of an open flame.
If you plan to install a fireplace in a gazebo, then its floor, walls and roof must be made of non-combustible materials. This can be tiles and steel panels. A gazebo with a fireplace in the center looks exotic and unusual, but you need to think carefully about the issue of smoke removal.

To make relaxing by the fire even more enjoyable and convenient, it is advisable to arrange an area around the fireplace. It would not be superfluous to carry out paving with tiles or stones, install comfortable furniture and a canopy.

How to choose a hearth design

Having decided on the construction site, you should choose the type of fire pit. Based on their location relative to the ground level, outbreaks are divided into surface and buried. Each of these design solutions has its pros and cons.

Thus, surface fire pits do not require excavation, and they are not in danger of being flooded by storm water. This type of fireplace can even be placed on the terrace, after first taking measures to protect its floor from sparks. A barbecue fireplace raised above the ground can be arranged beautifully and interestingly, making it the highlight of the yard landscape.

The good thing about a recessed hearth is that it does not need to be decorated and adapted to the design style of the site. The only difficulty will arise with providing air supply for the fire. This problem can be solved by installing an underground air duct or manipulating the placement of logs.

Let's look at some ideas with which you can build an original and practical hearth with your own hands.

Making a stone fire pit

For arrangement summer cottage it is advisable to use natural materials or their imitation. The shine of glass and steel is only appropriate in an office or city apartment. A stone hearth will look organic in any setting, without standing out against the background of greenery or snow-covered ground. For work you need to use only a special stone that is resistant to high temperatures. An ordinary cobblestone will immediately crack from the heat even during the first fire. The choice should be made on granite. It is better to purchase already chopped stones that are used to lay roads.

For work you will need the following tools and materials:

bayonet shovel;
Bulgarian;
level;
mallet;
Master OK;
clay;
sand;
buckets for water and solution;
gravel;
rags.

Making a stone fire pit is carried out in the following sequence:

Terrain tracing. A circle, square or rectangle is outlined, from which it is removed upper layer soil with turf and plant roots.
Arrangement of the base for paving stones. A ditch 30-35 cm deep is dug. Its bottom is leveled and compacted. A mixture of gravel and sand is poured into the trench. Another ramming is underway.
A solution of sand and clay is mixed. It is laid out on a well-moistened sandy base. The layer thickness must be at least 10 cm. Pipes are installed to supply air to the combustion space. Better to use steel pipes with a diameter of 50 mm. They are easy to clean after becoming clogged with ash and debris, and their service life is virtually unlimited.
Paving stones are laid on the solution. The grooves between the stones are filled with clay mortar. The excess is collected with a trowel and rags. Large openings can be covered with medium pebbles.
The internal and top part hearth. For this purpose, the clay mortar already used in the masonry is used. It is advisable to polish the inside of the firebox until it shines. This will make it much more convenient to clean it of soot.

You can decorate the finished fire pit with stone tiles, cut into straight or curved strips. This will not only decorate the fireplace for the cauldron, but also expand its functionality. You can place mugs and plates on the shelf. Their contents will remain warm for a long time even in winter cold.

A stone fire pit does not require any maintenance. After the first fire, the clay hardens and crystallizes. She will no longer be afraid of moisture. Any, even the most stubborn dirt can be easily washed off granite. To keep the fireplace sparkling clean, it is enough to occasionally treat it with soapy water.

Building a fireplace with bricks

It is immediately necessary to make a reservation that to create a firebox you need to use only fireclay (fireproof) bricks. Ordinary material left over after building a house will last no more than one season. Under the influence of heat, standard bricks crack, in the fall water gets into the cracks, and in winter the masonry collapses due to expansion of ice in the grooves.

In order to build a fire pit for a brick cauldron, you will need:

Bulgarian;
roulette;
oil level;
bayonet shovel;
hammer drill with mixer;
Master OK;
set of steel spatulas;
abrasive mesh;
facade plaster;
heat-resistant powder paint.

A brick fireplace is built in the following sequence:

Arrangement of a reliable foundation. Brickwork can have a mass of up to a ton. To prevent subsidence and destruction of the walls, a strong foundation is needed. Its depth should be at the level of soil freezing. You can save on material and time if you use reinforced concrete slab factory made. If there are problems with its delivery, then you can cast the slab yourself using reinforcement, sand, crushed stone and cement.
Laying out the walls of the fire pit. This is done while maintaining the alignment of the bricks vertically and horizontally. To bind the stones, a mixture of sand, clay, water and cement is used. The laid walls must remain undisturbed for at least three days for the solution to completely harden.
Finishing the walls of the hearth. From the inside it is simply coated with a mixture of clay and sand. Designing the appearance requires a more thoughtful approach. The outside walls of the firebox are finished facade plaster, lined with heat-resistant ceramic tiles or small stones.

To give the brick hearth more strength, stones can be laid around the perimeter of a pre-welded metal frame.

Manufacturing of metal structures

In every household there is always a lot of available materials that can be used in landscaping a summer cottage. The solution that lies on the surface is the construction of fire pits from disks of various origins. An excellent option is to use rims from heavy-duty vehicle wheels. These products are made of thick steel, which is resistant to mechanical and thermal stress.

To others interesting solution is the hearth from the drum washing machine. But its adoption must be taken rather carefully. The steel in the drum is very thin; it will quickly burn out from exposure to an open flame. The drum can only be used as a template for laying heat-resistant material.

To make a hearth from a disk, you need to have the following:

bayonet shovel;
level;
hammer;
manual tamper;
Master OK;
fireclay brick;
clay and sand;
facing material.

Steel rings are highly resistant to external pressure. It is advisable to make recessed type hearths from them. Iron is perfectly cleaned of soot and soot and can withstand exposure to damp for decades without visible damage.

The construction of fire pits from steel rings is carried out in the following sequence:

Excerpt from the pit. It should be made 10-15 cm wider and deeper than the planned depth of the steel product. The bottom of the pit is cleared of large roots, leveled and compacted.
Geotextiles are laid at the bottom of the pit, and fine crushed stone and sand are poured. This mixture is well wetted, leveled and compacted.
The steel ring is being installed. It is leveled, sand is poured into the gap between its walls and the pit. As the sand is backfilled, it is wetted and compacted.
Along the iron rim it is laid out finishing material. It is best to use fireclay bricks for this. It needs to be fastened with clay mortar.

The final stage is to create a border along the upper edge of the masonry. It will not only make the masonry more convenient, but will also hide the internal steel walls.

Reading time ≈ 3 minutes

Each owner country house or a summer residence, you want to be able to light a live fire in your area and sit by the fire on a warm evening, frying something edible over the fire. How to organize a fire without leaving black fire marks on the lawn, with maximum comfort and safety? Make sure that the hearth fits harmoniously into the garden plot, its design is pleasing to the eye and the arrangement is within the power of the owner himself?

To build a fireplace in a dacha with your own hands, as in the photo, without turning to the services of professionals, is quite possible even for a person who initially has a very vague idea of such things. construction work. The main thing is to follow the sequence of work on arranging the hearth, as well as a sensible choice of materials.

Plan

Having set out to set up a fireplace at the dacha, it is advisable to draw a diagram or drawing of it on paper. Before starting work, it is important to clearly think through where the future hearth will be located, and also to mark the selected location for it. Marking the fireplace at the dacha, guided by ready-made plan, make it easier and more convenient. For marking, you will need the following tools: tape measure, pegs, plumb line and a ball of twine.

Digging a hole and preparing a concrete mixture

Having marked the place, a hole 50-60 cm deep is dug in the ground. Afterwards, concrete should be mixed with fine crushed stone.

The approximate composition of the mixture is taken from the calculation: for 45 kg of sand - 30 kg of crushed stone and 15 kg of cement, water is added until the required mobility of the mixture. Alternatively, you can take ready-made concrete mixture stamps 100.

Selection of stones and their placement

The contours of the hearth itself are laid out from stones at the bottom of the pit, simultaneously securing them with concrete mortar.

To create a fireplace you will need flat stones 5-10 cm thick various sizes. Stones can be very different (with the exception of porous shell rocks and limestones).

Based on texture, you can choose completely unique combinations of stones, focusing on your taste. If choosing stones, as well as their layout, is difficult to do on your own, you can enlist the help of a designer or a person with artistic skills in this matter.

Technological nuances

The bottom of the fireplace is also made of a concrete pad at least 10 cm thick. Holes are left in the concrete itself to drain rainwater. If necessary, the holes can be used for installation various designs for frying meat and grilled vegetables.

The sinuses from the outer walls of the fireplace are filled with excavated soil and compacted.

At the same time, backfilling is done in such a way that there remains a space under a thickness of 10-15 cm to the level of the top of the soil. To do this, concrete is laid around the hearth with large flat stones embedded in it.

It’s hard to imagine how many people delightedly admired the burning of logs, sitting near the fire. A fire pit at the dacha, made with your own hands, allows you to provide such pleasure at any time, and even in the company of friends. Blazing firewood is mesmerizing and has a wonderful psychological effect.

The fire pit must be located 3 meters from buildings and 4 meters from tree crowns.

A fire pit at the dacha, made with your own hands, can become both a barbecue grill and a barbecue. The aroma of food cooked over a fire is difficult to compare with anything. A fire pit can be built quite easily on suburban area, but it is also important to ensure complete fire safety for both buildings and the surrounding nature.

Features of a country fire pit

The barrel fire pit can also be used as a grill and barbecue.

A country fire pit is an open street hearth, made with your own hands, in the open area of the dacha. Such a fire allows you to cook some types of dishes and keep warm, and is also often the center of a recreation area in evening time. The fireplace at the dacha should ensure that the logs burn in the form of a sufficiently high flame, but at the same time not pose a threat to the fire of buildings or plants. Appearance the fire pit must fit into the overall country house design and even decorate it.

The place for a permanent fire should be located at a distance from buildings and plantings, and there should be no grass in the fire area. When placing a fire in a garden, the fire should be removed from the crown of trees or bushes at a distance of at least 4 m. The fireplace should be removed from buildings by more than 3 m. You should not choose a place for the fireplace on the leeward side and do not light it in windy weather. In this regard, it is not recommended to make a fireplace with your own hands on a hill.

The optimal location for a fire pit is a flat area at a level slightly lower than the level of the buildings. Most often, the fire pit is shaped like a circle with a diameter of 80-100 cm, around which stationary benches are installed for sitting. There may be a place to store logs at a safe distance from the flame. The area itself where wood is burned must be lined with non-combustible materials.

Structurally, a fire pit can have several types: a hearth buried in the ground, outdoor version, protected by walls, and external version open type(bonfire). Construction of any type begins with cutting off the top layer of turf, clearing the soil of roots and covering the soil with heat-resistant material.

Tools required for work

Rice. 1. The resulting gap must be filled with gravel.

When making a fire pit at your dacha with your own hands, you will need the following tools:

Bulgarian;
electric drill;
hacksaw for metal;
mallet;
hammer;
chisel;
chisel;
metal scissors;
putty knife;
Master OK;
shovel;
vibrator;
construction mixer;
pliers;
vice;
roulette;
metal ruler;
construction level.

Buried fire pit

Rice. 2. Diagram of a buried fire pit

A recessed version of a country fire pit can be made as follows: a hole about 40 cm deep is dug, and then fine gravel 15 cm thick is poured onto the bottom. The hearth frame is made of block stone or brick, the elements are laid on clay mortar or fireplace adhesive composition. After laying the first layer, it is carefully leveled by tapping with a mallet. inner ring, formed first next to the masonry, filled with crushed stone with a tamper. Then the remaining elements are laid in a circle. The topmost masonry row is made on the ground surface and is made of decorative stone.

Inside the fireplace it is recommended to install a metal screen in the form of a cylinder formed from metal sheet 1-2 mm thick. The external gap between the wall and the soil is filled with soil previously removed from the pit. The layout of a buried fire pit is shown in Fig. 2.

The next stage of arrangement is the creation of a protective area around the fire pit. To prevent the flame from spreading beyond the source zone, a flat platform is constructed, paved with stone, tiles, bricks, paving stones or filled with concrete. Benches are provided at this site to accommodate people. The dimensions of the area are based on the assumption that a person is located at least 80 cm from the fire.

IN daytime such a hearth can be used for cooking. To do this, a tripod is installed above the equipped pit and a pot is suspended. Among other options for constructing a buried fire pit, the following technology can be noted: a cone-shaped depression is made in the pit (expanding upward), the cone is concreted, and the top is lined with decorative ceramic tiles.

Outdoor fire pit

Rice. 3. Stages of creating an outdoor fire pit

The most simple type outdoor fire is an open fire, which is lit in a designated place. Such a place can be equipped with reliable protection from the wind and other natural or artificial obstacles. In this case, in a circle with a diameter of about 1 m, the turf layer of earth (about 10 cm thick) is removed, and the formed hole is filled with crushed stone, ash, stone chips or other non-combustible fine materials. Around the area arranged in this way, pebbles of at least 10 cm in size are installed to create volume for laying the logs. The area around the fire pit is formed in the same way as described. Such a fire requires special care during operation.

The option of an outdoor fire pit is considered more reliable and safe. closed view. The principle of this design is the construction of a cylinder above the surface of the earth in which a fire is lit.

The foundation for the structure is prepared in the same way as for an open fire. Then a metal rim with a diameter of at least 40 cm and a height of more than 30 cm is installed in the circle. The drum of an old washing machine, a cut metal barrel, etc. can serve as improvised materials. In Fig. Figure 3 shows a diagram of the installation of such a fire pit.

Along the outer circle of the metal cylinder, masonry thickness of at least 10 cm. For this purpose, you can use refractory bricks, ready-made concrete blocks, paving slabs, border elements, purchased blocks from natural stone. When laying, you should use a clay stove mortar or a special fireplace adhesive composition. The gap between the metal and the stone is filled with the same solution or sand.

Fireplace made of metal strips

Another method of making an outdoor closed fire pit is gaining popularity - a hearth made of metal strips. This design is made from two pieces of corrugated galvanized steel. The design diagram is shown in Fig. 1.

From steel sheet 2 tapes with a width of at least 30 cm are cut out so that they form two cylinders with a gap of 10-15 cm between them. The tapes are bent in a circle, and their ends are connected with nuts. The cylinders are fixed in a circle on the ground, and fine mineral non-combustible material mixed with sand is poured between them. A layer of gravel up to 10 cm thick is poured into the internal cavity of the cylinder.

On top of the inter-cylinder backfill, you can make plaster and cladding at your discretion.

Economical design

One of the cheapest DIY designs for country fire pits is the outdoor version made from a metal barrel. In general, the entire complex is manufactured as follows: a circle with a diameter of 0.8-1 m is formed according to the described method, a piece of a metal barrel without a bottom (about 50 cm in diameter and 30-40 cm in height) is installed on it. A layer of up to 10 cm of gravel is poured inside the barrel. A conical bevel of gravel with a base diameter of about 1.1-1.3 m is made around the barrel. The bevel is filled with concrete 2-3 cm thick, then the entire area around the fire is concreted (diameter - 2. 5-3 m). A removable cooking grate should be provided on top of the barrel.

The area under the fire pit can become a recreation area with attractive design. You can create an original area with a center in the form of a fire pit, which will allow all family members to relax in nature.

A fire pit in landscape design is wonderful decorative element, which will decorate your summer cottage, adding harmony to the environment. In addition, a fireplace at the dacha will also serve as a practical option, because every spring and autumn personal plot Trees are cut down, leaves and debris accumulated over the winter are collected. All this is burned in a common heap, and sometimes such an unfenced fire pit can be completely unsafe.

What types of outbreaks are there?

Foci can be of 3 types: open, deep and closed. They can be purchased in specialized stores, ordered from craftsmen, or made with your own hands.

The deepest (earthen) type of fire pit is considered the safest. For the hearth, a depression is made in the ground, which is reinforced with stone or concrete. The fire is lit in this bowl. If you have chosen this type, then you need to know that in this case there may not be enough oxygen for a good flame, moreover, such a fireplace must have shelter from precipitation.

Making a fireplace in a dacha with your own hands using an open principle is the easiest way; you don’t need any special skills for this, and such a fire pit will look very beautiful. Most often, for this, a paved circle of any diameter is made, in the middle of which a shallow hole is dug, which is also lined with brick or stone. The diameter of the circle depends on your preferences, but it is not safe to make it smaller than 2 m. It is better to make the circle wide so that it not only serves as protection against the spread of fire, but also serves as a platform on which you can install a table or benches.

An enclosed fireplace can be completely varied in shape. To install it, you also need to pave the area for fire safety, and already install the structure on it. Nowadays, an enclosed fire pit in the form of a Russian stove is becoming increasingly popular.

There are also portable fireplaces - you can easily install this option where this moment want to see him. At its core, it is a table and a bowl for a fire; if desired, it can be covered with tempered glass or an additional barbecue grill can be made. If you are a metalworker, such a fire pit will be wonderful even without fire. stylish decoration your summer cottage. The table can be laid out with decorative tiled mosaics, and the metal fire pit itself can be complemented with beautiful forging.

Choosing a place for a fire pit

In the question of how to make a fire pit yourself, you need to approach the problem of its location with all responsibility. A place for a fire in a country house is important question. After all we're talking about about open fire, which means it should be removed from outbuildings, children's playgrounds and, in fact, the house itself. You also need to make sure that sparks from the fire will not reach the trees or the fence (if it is wooden). To prevent the fireplace from having to be constantly cleaned of water, do not choose low-lying or insufficiently well-drained places, however, it is better not to place the fireplace on a hill.

How to do everything yourself?

It may seem surprising to you, but making a fireplace in your country house with your own hands is not as difficult as it seems. In addition, it can be made not just a place of warmth and comfort, but the main element in the recreation area. Around the hearth you can install benches, a small table or a whole cafe with a tabletop for cutting meat, a wood storage area and a large table for friendly company.

Although there are now sets on sale that include a bowl and stones for decoration, it is more pleasant to sit by your own individual fire. Therefore, stones can be collected from a river or mountains, and a bowl can be made from an old leaky barrel, which is found at every dacha.

After choosing a location, you need to decide on the size of the fire pit. To do this, place the bowl in the center and lay out the area with stones. To mark the boundaries, you need to remove the last stones and draw arcs with paint, then remove all the stones and connect the arcs into a circle.

Where you have marked a place for the bowl, you need to dig a hole of about 15 cm. If you have dense soil at your dacha, then in addition to a shovel you may need some other device: a hoe or even a hammer with a chisel, but don’t give up - a hole you need a shallow one.

When you have finished the hole, you will need to pour gravel into it so as to almost completely cover the depression. This is very important point— gravel is needed to prevent your fire pit from flooding when it rains. This is a kind of drainage.

Nowadays there are no problems with stones for landscaping in stores. If you decide to buy stones, then their choice depends only on your taste, imagination and wallet. However, keep in mind that the color and texture of the stones must match the overall concept of your dacha. The stones will need to be laid along the edge of the gravel. To keep row 1 even, you can place a bowl, but then you will need to remove it. You can adjust the height of the stones and make the distance between them minimal using rubber mallet. Lay the 2nd row of stones so that the middle of the stone is at the junction of 2 stones from the 1st row. Lay out subsequent layers in the same way. In order for the stones to adhere to each other, you need to use a solution of clay or lime. Do not use cement, which is not suitable in this case - it will crack from the heat and the stones will fall. After laying out the stones, place the bowl in the center.

Another option

Even easier is to make a portable hearth in the form of a barrel. Of course, it will be a bit difficult to carry it back and forth every day, but if you really need it, then you can. For a portable fireplace you will need metal barrel and circle. Place a piece of metal on the barrel and cut smooth circle, retreating from the barrel itself by 40-50 cm. In the center of this circle you will need to cut 1 more circle, but it should be flush with the diameter of the barrel. Place the circle on the barrel, secure it and paint it with spray paint. Pour gravel inside the barrel, not reaching the edge of 40 cm. That's it, the fire pit is ready - you have a hearth framed by a small table on which you can place a cup of coffee. The barrel itself can be decorated like wood (covered with boards and fastened with metal rings) or lined with pebbles.

Site decoration

In order to pave the area around the fireplace, suitable various materials: tiles for paths, pebbles, gravel. But, of course, the slabs look most impressive irregular shape, which are arranged in a chaotic or bizarre pattern. Choose wide slabs - then it will be convenient for you to place on them garden furniture. A circular bench around the fireplace looks very nice and cozy. If desired, the back of the bench can be built from the same stone as the fire pit, but do not make it high - a maximum of 50 cm.

The firewood rack looks very nice and cozy next to the fireplace, and it’s also very convenient. If you install a fire pit near the pool, it will serve not only as a place for warmth and roasted meat, but also as lighting, but do not forget that the ashes will fly into different sides, including in the water.

In any case, in a suburban area during the warm season there will be some garbage that needs to be burned or it will simply be unnecessary things. And here it becomes important how to arrange a place for a fire in the countryside so that the wind cannot fan sparks, which could cause a fire.

This question is most relevant in areas where wooden buildings(even if not at home, but utility rooms), where in windy weather an open fire poses a particular danger. Making a protective structure in this case is not very difficult - we will talk about it below and show you a video in this article.

Fire pit

Note. The word “bonfire” in most cases means a place for a fire in a country house or other place, made specifically for this purpose, or left after the combustion of fuel.
This word can also mean a large fire.

What is it for

An open fire in a suburban area is usually lit for three reasons:

firstly, this is the usual disposal of unnecessary things and garbage;
secondly - for aesthetic purposes, that is, to simply sit by an open fire in the fresh air;
thirdly - for arrangement.

Of course, safety will come first and it doesn’t matter at all whether there are people around country houses made from block containers, brick or wood - there will always be material that poses a fire hazard.

Of course, if you cook barbecue, you will use only firewood as fuel; it is also more likely that you will use wood for the aesthetic enjoyment of the fire. But when burning garbage, different materials can get there.

Therefore, you should make sure that explosive objects, for example, cans of paint and aerosols, do not get into the fire - the instructions warn about their explosiveness. You should also avoid burning rubber and plastic (bottles, bowls, toys, etc.) - the rubber will smoke, depositing flakes of soot on neighbors' property, and polymers release toxins when burned.

Arrangement options

First of all, to equip a place for a fire, you will have to find a good place, which should be located away from a residential building, utility buildings and the crown of spreading trees.
In addition, you should not use the lowest or highest points of your site- it’s best if you settle on something in between and the site turns out to be open and clearly visible.

Most often used for hearths round form, but this is by no means the main requirement - it could also be:

square;
rectangle;
and even a triangle.

The main thing is that its section is in the very bottleneck, where the firewood will burn, was at least 40 cm. For a circle, a diameter of 80-100 cm is usually used, although this is not something mandatory.

Aboveground hearth

Typically done with decorative finishing. Although a metal rim can be inserted into the middle, its walls must be at least 1-1.5 mm, otherwise it will burn out. That is, a metal bowl will not work here.
You can also install a concrete circle in the center, which you will then finish paving slabs, only as an adhesive you will need special mixtures with fireclay additives.

You can also lay out the walls from fireclay (fireproof) bricks; ordinary clay with the addition of fireclay powder is used to bind it.
Or, instead of bricks, you can use granite cobblestones, which will be sufficiently firmly fixed in the ground or in concrete screed, and small gaps between them do not need to be sealed at all - this will not interfere with combustion.
The walls and the site itself can be finished using any facing materials, which are not subject to melting and are not afraid of open fire.

The recessed hearth that you see in the photo above is very similar in technological design - they use similar materials, and the cross-section of the fire pit itself does not differ from the above-ground version. The main difference is the aesthetic perception of the object and personal preferences.

To set up a buried fire pit:

A hole is dug 30-40 cm deep and a cushion 15-20 cm high of fine crushed stone or granite screenings is poured into it (some use fine-grained expanded clay for this purpose).
The walls can be laid from refractory bricks, hewn or simply smooth granite, using clay with fireclay powder for binding.
You can also take a simpler route and put it in a hole concrete ring- the main thing is that the upper part of the walls is strictly horizontal. The bottom can be concreted.

Brick fire pit. How to organize a garden hearth at home and in the country? Option #1 - above-ground structure