What is meant by a fireplace?

A fireplace is a chamber, made of different materials usually constructed to contain the fire for various applications. A fireplace is often known as a hearth. Fireplaces can be made of bricks, steel, stone, and concrete. Fireplaces serve as room heaters for cold areas and vary in design and heat efficiency.

The development of fireplaces changed over time. Initially, they were meant for relaxing, dwelling, cooking, and heating water for laundry and bathing purposes. A typical fireplace or a hearth contains a firebox or a pit that contains the fire. The smoke of the combustion is made to escape out through a chimney. A fireplace may be inside or outside a commercial building and mainly composed of a fire pit, chimney, foundation, a mental, chimney crane, grate, lintel, a lintel bar, over mental, damper, smoke chamber, throat, flue, chimney filter, and afterburner.

In this article, a brief introduction about the different fireplace components, different materials used in the construction of a fireplace, and different fuels that power a fireplace has been outlined.

Fireplace terms

The different components of a fireplace have been outlined below.

Firebox

A firebox is the main component of a fireplace where the fire is built. A firebox may have a square dimension or a rectangular dimension. The fireplace is purposefully surrounded by fire-resistant materials to shield the fire from igniting other materials. The front of the firebox is known as fireplace opening, which may or may not have doors made of steel nets.

Hearth

The base of a fireplace is known as the hearth. The hearth usually extends outwards into the room and contains the grate. The materials are supplied to the hearth and it is the place where the fire is contained. The part of the hearth which is in contact with the fire is sometimes known as the inner hearth and the part away from the fire extending outwards is known as the outer hearth.

Mantel

A mantel can be generally found at the top of the fireplace. Mantel prevents the smoke of the fire to reach the room. A mantel generally extends outwards into the room and acts as a shelf for storing essential items.

Lintel

The lintel is located at the top of the fireplace section. It is located between the throat and the chimney of a fireplace. The lintel provides structural support to the chimney and helps in bearing the load of the chimney.

Chimney throat

It is the component found at the intersection between the chimney and the firebox. The chimney throat collects the smoke and directs it towards the chimney.

Fireplace damper

A fireplace damper is a door with a mechanism. The damper may be provided at the fireplace elevation or near to the chimney throat. It helps in maintaining the heat content of the fireplace when the fireplace is not in use.

Ash dump

An ash dump or an ash pit is found underneath the fireplace. The primary purpose of an ash dump is to collect the ashes of the burnt materials which can be used later. Not all fireplaces have an ash dump, but instead, they are provided with a small basement and a clean-out door.

Chimney

The chimney is a tall freestanding structure, which lets the combustible smoke escape out to the ambient. The top of the chimney is provided with a chimney filter to entrap debris and other polluting materials. Sometimes, a chimney is also provided with a chimney cap which restricts animals to take shelter inside the chimney. It also stops water to enter the fireplace during rainy seasons.

Smoke chamber and smoke shelf

The work of a smoke chamber is to compress the combustion products before letting them move towards the chimney. The smoke shelf ensures none of the outside debris, including water droplets, directly makes its way into the firebox.

Fireplace construction procedure

This section outlines the general construction procedure of a typical fireplace.

• The construction of a fireplace starts with the location of the fireplace section. Fireplaces liberate excess heat. Hence, the preferred fireplace section should be at the safest place of the building.
• Based on the building construction, the foundation of the fireplace is built. If the fireplace is pre-planned, the foundation is constructed during the construction of the building itself with flexibility for outdoor fireplace construction plans.
• A strong hearth is built with proper reinforcements and ventilation. The slab of the hearth is made with concrete and lined with refractory bricks. The slab of the hearth is sometimes given a height to increase the fireplace elevation. Refractory bricks are special bricks that can withstand high temperatures and provide more resistance to thermal cracking.
• The inner hearth structure is further lined with refractory non-combustible bricks and masonry joints.
• The combustion chambers are made with normal masonry and mortars and they should be lined with fire-resistant materials as much as possible.
• The combustion chamber should be constructed of 100 mm thick bricks and the mortar joints should have a minimum thickness of 6.4 mm.
• The mantel that shields the room from the combustible fuel should be made at least 6 inches away from the firebox.

Types of fireplaces

Fireplaces are usually of three types- masonry fireplace, prefabricated, and gas type fireplace.

Masonry fireplace

Masonry fireplaces are common and form an integral part most of households. They are also known as wood-burning fireplaces.

Prefabricated fireplace

Prefabricated fireplaces are usually lightweight enclosures and are placed directly above the concrete or hardwood and a few inches away from the wall. These kinds of fireplaces always remain cool. These fireplaces are cheap and very easy to install but are extremely sensitive and require utmost care during operation.

Gas fireplace

Gas fireplaces are the modernized fireplaces used in modern buildings and are made as an alternative to masonry fireplaces. These fireplaces make use of natural gas, the fuel for combustion with an electrical system for creating a spark to initiate combustion. A suitable arrester surge is provided to safeguard from over-voltage.

Context and Applications

This topic is usually taught in most of the undergraduate and postgraduate degree courses of:

• Bachelors of Technology in Civil Engineering
• Masters of Technology in Civil Engineering
• Masters of Technology in Building Construction

Practice Problems

1. Which of the following is a material used in fireplace construction?

1. Cinder
2. Masonry
3. Bricks
4. Both b and c

Answer: Option d

Explanation: Masonry and bricks, both are the materials used for fireplace construction.

2. Which of the following is the base of a fireplace?

1. Fireplace elevation ground
2. Hearth
3. Firebox
4. Throat

Answer: Option b

Explanation: The hearth forms the base of a fireplace.

3. Which of the following fuel is used in a gas-type fireplace?

1. Natural gas
2. Wood
3. Petroleum gas
4. All of these

Answer: Option a

Explanation: A gas-type fireplace uses natural gas as the combustible fuel.

4. What is the other name of the masonry fireplace?

1. Mortar fireplace
2. Building fireplace
3. Wood-burning fireplace
4. Concrete fireplace

Answer: Option c

Explanation: The other name of the masonry fireplace is the wood-burning fireplace.

5. Which of the following is the freestanding structure of a fireplace?

1. Chimney
2. Outer mantel
3. Firebox
4. All of these

Answer: Option a

Explanation: A chimney is the freestanding structure of a fireplace.