- History of fireplaces
- Classification of wood burning fireplaces
- Characteristics of open and closed fireplaces
In this article: a history of improving fireplaces; styles and types of construction of wood-burning fireplaces; open and closed firebox – aesthetic beauty of the flame or emphasis on heating and safety.
Compared to the life of great-great-grandfathers and great-great-grandmothers, our generation of the 21st century is pretty spoiled with heating devices – central heating and various electric heaters, stoves, which are both powerful and economical. It would seem, what more could you want? However, there is one point: modern heating devices are good for everyone, except for one thing – for the most part they are boring, because for all their functional abilities, they do not decorate the room in any way. And for this reason, one old type of stove is always popular both a century ago and today. Probably, it’s all about the magic dance of fire, because fireplaces are an amazing tool for relaxation.
History of fireplaces
Open hearth, and this is how it is translated from Latin “fireplace” (caminus), Over the centuries, a number of improvements have gone through – from a fire to a full-fledged heat generator stove. The first hearth was a hole in the earthen floor, on the sides of which were hammered wooden or metal racks to fix the boiler over the fire. The conveniences of such a hearth were the most minimal – it smoked mercilessly, sparks and coals scattered around the wooden hut, causing frequent fires. With the invention of a chimney over the hearth, the smoke problem was eliminated, but the heating quality became even worse – most of the heat went into the chimney, and the fires from accidental coals did not decrease. At the end of the 17th century, the German prince Rupert Rhine, nephew of King Charles I of England, invented a simple and effective improvement for the hearth – he installed a metal grate-grate in it, raised above the floor level with the help of legs or stones, and a fire was made on this grate. This measure made it possible to improve the combustion of fuel due to the flow of air to the coals..
In the 17th century, the design of the fireplace became as we know it today – the inventions of two American engineers significantly improved the quality of heating. Benjamin Franklin introduced a U-shaped cast iron partition into the fireplace device, causing the volatile combustion products in the fireplace to move upward, then down and up again in a curved channel. The Franklin baffle made it possible to increase radiant heat transfer and reduce heat loss through the chimney. And the second American, Benjamin Thompson, Earl of Rumford, completely changed the design of the fireplace that existed at that time, narrowing its side walls and expanding the firebox chamber in height, increasing the heating efficiency and ridding the room of combustion products, the full exhaust of which with the previous fireplace design was impossible.
Classification of wood burning fireplaces
We have decided on the type of fuel, so we will focus on the architectural styles and types of fireplace designs. Wood-burning fireplaces owe their architectural diversity especially to the past century – the high-tech and bionics styles developed in the 20th century. Let’s not get ahead of ourselves and start with a description of the classic architectural style..
For classic fireplacecharacteristic features are a portal in the form of the letter “P” and an open firebox, the use of natural stone, cast iron and wooden elements in its creation and decoration. Fireplaces in a classic style with an open hearth have low efficiency (no more than 20%), because air access to the firebox is not controlled and the fireplace acts rather as a pump for pumping air from the room outside the building than as a full-fledged heating device. Therefore, most modern classic fireplaces are equipped with a sliding or removable screen that closes the firebox portal and increases the heating intensity..
Rustic (country, rustic) style– the shape of the portal is “D” -shaped, such a fireplace is placed near the wall or in the corner. The construction and finishing materials of a rustic fireplace are inexpensive – usually shell rock or sandstone. The portal of such a fireplace is most often equipped with an independent wood niche..
Modern fireplace styles– high-tech, modernism and bionics. The first two styles are characterized by minimalism, nevertheless, this does not limit design solutions, allowing you to create portals of an amazing shape that combine stone, metal and glass in their design. The architecture of the bionics style is based on the forms that exist in natural nature – the almost complete absence of straight lines and angles, an elusive sense of movement in each line. Fireplace portals made in the bionic style are real masterpieces of art.
By the type of construction, wood-burning fireplaces are divided into English (closed), Rumford, alpine (open), half-open and equipped with a built-in firebox. The characteristic features of an English fireplace are a straight chimney and a small brick or stone furnace (cast iron furnaces are designed for burning coal), made in strictly straight lines.
Fuel chamber in fireplaces of Rumfordhas a shallower depth and twice the height than in English fireplaces, which allows the flame not only to heat, but also to illuminate the room. The smoke tooth is absent, it is replaced by the oval Rumford throat, the ascending narrowing of which ends with a damper, the degree of openness of which can be controlled, thereby increasing or decreasing the draft in the chimney. Fireplaces of the Rumford design have a higher heat transfer than other types of fireplaces with an open hearth.
Alpine fireplacein its essence, it is difficult to call a fireplace – it is rather a hearth, the firebox of which is located at a considerable distance from the walls and is not connected with the chimney, the bell of which hangs over the hearth bowl. For heating purposes, open (island) fireplaces are not suitable, because most of the heat escapes into the pipe. Such fireplaces are created exclusively for aesthetic purposes – you can watch a bright flame from anywhere in the room, there are no obstacles to this.
The design of the fireplace, in which it is not built into the wall, but is erected close to it as an extension, is called half-open. At the same time, the order can correspond to a Rumford fireplace or an English one, the main advantage of such fireplaces is regardless of the walls, which allows them to be erected without altering the latter.
Fireplaces with built-in insertdiffer from those described above in that the firebox is not laid out in them, but is built in finished form – in fact, this is no longer the construction of a fireplace, but a brick or stone finishing of the finished firebox, capable of working without external finishing. The body of the built-in insert-cassettes is made of cast iron or high-carbon steel, they are equipped with a door with heat-resistant glass inserted into a metal frame. Developed in the 20th century, wood-burning fireplace inserts have high efficiency and are economical in fuel consumption; they successfully compete with classic fireplace inserts.
In addition to the types of fireplaces described, there are also fireplace stoves, combining a fireplace insert and a hob. The location of the hob can be either above the fireplace insert, or on the side or on the back of the stove, which makes it possible to bring the fireplace insert to one room, and the hob to another, separated from the first by a wall. Due to the combination of two functions (fireplace and stove), such brick structures have a massive structure and take up a lot of space, ready-made metal fireplace stoves are more compact.
Characteristics of open and closed fireplaces
Which type of fireplace is better – open or closed firebox? In the classic version, the fireplace insert is not closed by any partition except perhaps with a metal grate. Modern fireplaces usually have a closed firebox to some extent – consider the pros and cons of both types of fireboxes.
Advantages of an open hearth:
- open flame, the observation of which gives aesthetic pleasure to those present in the fireplace room;
- radiant heating, permissible only with an open fireplace, is felt immediately after kindling – no need to wait until the walls of the firebox warm up;
- from the point of view of room design, an open fireplace insert looks impressive and harmonious;
- this firebox can be used for cooking meat products on a spit.
Open firebox – disadvantages:
- low efficiency, not exceeding 20%. It makes no sense to use fireplaces with an open hearth for heating in a harsh climate, because it will heat only as long as a fire is burning in the firebox (heat accumulation by the body of such a fireplace is minimal);
- it is necessary to constantly monitor the burning of firewood, since in the absence of a screen (the metal grate does not count), coals falling out of the hearth and flying sparks can cause a fire. There is a possibility of carbon monoxide and smoke entering the room due to back draft, especially in strong winds and fogs;
- the combustion process in an open fireplace firebox requires a significant amount of air drawn from the room, therefore the fireplace room must be large, otherwise the reverse process is inevitable – not heating, but cooling the room due to the constant flow of cold air into it from the street.
A fireplace with a closed hearth also has its pros and cons. Let’s start with the pros:
- high efficiency, reaching 65-70%, which allows it to be used for full heating of a room in the cold season;
- low air consumption and economical fuel consumption;
- if there are air ducts and a convection casing in the structure, several rooms can be heated, i.e. can be used like a conventional oven;
- a closed firebox with a door swinging up and fixed in this position can be used as an open firebox;
- the firebox door is a reliable barrier for sparks and coals, in addition, if the homeowner’s family has small children, they are guaranteed not to get to an open flame and not get burned.
Cons of a closed fireplace insert:
- allows only convection heating, which causes the movement of the air mass inside the room, as a consequence of this – the constant presence of dust in the air;
- if there are no built-in heat accumulators, then heat transfer stops shortly after the flame in the furnace has died out;
- it is difficult to integrate a closed firebox into portals with rich finishes, primarily due to the distortion of the style. In addition, the screen door swinging upwards will require a lot of space and you will have to either raise the mantel above the usual one, or recessed the firebox below the portal window. You can use doors that open to the side, but in this case it will not be possible to leave them open to observe the flame in the hearth – they will interfere.
The question of the final choice of the type of fireplace insert, the design and style of the fireplace depends on the goals that the future owner sets for the fireplace. The main thing is that the house will have its own fireplace portal and flashes of flame will fill the evenings with new meaning …