Modern buildings are complex and sophisticated in design, compared to those of a decade ago; therefore, it is important for a designer to bear this factor in mind when designing effective fire walls. The complexity of modern buildings is the main reason behind the lack of detailed information among designers.In order to meet all constructions specifications required their is need for designers to be updated and equipped as far as building knowledge is concerned.
According to Cooke, (2007) a building designer must consider the following factors when designing and building fire walls; whether there is need for a protection zone, the security of the building and modifications of the wall and the building.
A fire wall is often used internally to create fire compartment partitions within a building or externally in order to prevent external fires from reaching or affecting the property. Such fires may be accidental or malicious.Larger buildings with corresponding elevated fire walls have led designers to manufacture lightweight walls to avoid overloading the foundation. Towering fire walls should not only be fire resistant with rock wool cores but should be well insulated and rapidly erected. Steel faced layered panels are the preferred application for towering fire walls.A sound fire safety plan takes into consideration the consequences of a fire wall on environmental pollution, human and animal safety, protection of heritage, loss of goods and business continuity. This plan should also be in accordance with the stipulations of the fire safety engineering (Cooke, 2007).
A good fire wall normally possesses the essentials of fire resistant conditions such as stability, insulation, and integrity. These essentials are easily identified when put to test under the regular fire resistance exposure check, referred to as ISO 834 time-temperature relation. The duration of time required can be decided by referring to Approved Document B ‘Fire Safety’. Either by a competent fire safety engineer, who is well equipped with the information on the severity of fires in buildings or by the insurance company. In order to protect a building from radiated fire in adjacent buildings, fire risks need to be calculated. This can be done using the configuration ideas demonstrated in the BRE report 187.
It is also important to create a fire protection zone; this is done by establishing an additional external wall as well as roof on either side in order to create a fire block. The intersection at the edge of the fire wall should be of a good fire integrity order to create room for any thermal buckle, which may arise in a fire. The protection zone applies in scenarios where fires start from the roof then spread to the walls. However, the materials used in the building of these walls should not be made from materials that melt or produce flaming drops once heated. Although it is an expensive method and the fire walls are likely to collapse when the fire is intense, it is also highly effective as far as life safety is concerned (Cooke, 2007).The fire wall should not be able to collapse due to pressure from adjoining roof or affected by buckles of the roof. In construction of the fire wall, the sandwich panels should have a 300mm wide full depth fireproof material that cannot be burned and should include a layer of steel in order to strengthen the wall. The fire walls and roof should also withstand all manner of weather conditions especially winter.
Designers should consider the security within the building when designing fire walls .In order to counteract fire explosions or multiple fires started for malicious reasons, a builder may use layered panels with stone wool cores. People working in different fire department may require different access features; this can be done to increase security. When making the fire wall, builders should make sure that the materials are not wet and dirty. Such a wall should be able to withstand strong winds during installations and after the construction of buildings. It should also be repairable. (Cooke, 2007)
The fire walls should be well able to allow for internal changes such as repositioning of doors, additions of new rooms. Ducts that pass through the wall should be avoided to prevent weakening the wall. The insurance company should declare fire walls fit for use. If the wall was examined for fire resistant when the panels where horizontally oriented, it should also be tested when the panels are vertically oriented. Competent engineers must carry out all tests.