Investigation of Energy-Efficient Façade Systems in the Context of Fire Safety

Evser Civelek and Figen Beyhan

#### Abstract

Studies on energy efficiency, which has changed the agenda of all the countries of the world which caused significant changes in the design approaches of the structures and caused significant changes and many different applications, were realized on energy-efficient façade systems. These façade systems, which have been extremely successful in the efficient use and conservation of energy, unfortunately do not provide adequate and competent solutions when it comes to fire safety. The aim of this study is to examine the design and application details of energy-efficient façade systems in which weak points in terms of fire safety are to be determined. Also fire safety measures are to be taken by taking into consideration the legislative obligations related to the application details of the façade construction materials. For this purpose, firstly, the material finishing systems which are widely used in the façades to ensure energy efficiency will be examined. Fire propagation paths will be investigated which occurred Turkey on April 5, 2018, at the Istanbul Eyup Taksim Training and Research Hospital fire with the analysis made in terms of the provisions of national regulations, and then what should be related will be put forward.

Keywords: fire safety, combustible exterior wall systems, regulations, mechanism of fire spread

#### 1. Introduction

The concept of energy efficiency leads to many changes in the building sector and society and is seen as the main driving force in the built environment. The primary effort of the concept in question is the protection of the world and thus the survival of the people (energy, climate, ecosystems, etc.) while shaping the political, economic, and technological factors of the society as well as the country's legislation. The number of 5627 Energy Efficiency Law of May 2, 2007, in Turkey entered into force, and the effective use of energy, prevention of waste, alleviating of the energy cost burden on the economy, and energy sources for environmental protection and energy use were aimed at increasing productivity [1]. The studies on energy efficiency, which has changed the agenda of all the countries of the world, have caused significant changes in the design approaches of the buildings, and many different applications have been realized on energy-efficient façade systems. These façade systems, which have been extremely successful in the efficient use and conservation of energy, unfortunately do not provide sufficient performance when it comes to fire safety.

In terms of energy-efficient structure, façade systems are generally examined in two groups as single-layer curtain wall and double-shell curtain wall. It is common in both of these systems that insulating materials, which are critical in ensuring energy efficiency, can cause major catastrophes when necessary measures are not taken during fire. The most important problem to be experienced in such façades is when the fire by-products (smoke, hot gases, flame) are not controlled. As a matter of fact, gaps formed between two façades or between the façade and material gaps, the spatial geometry, the cross section of the cavity, the dimensions, the airflow rate, and the pressure of the ventilation system will be different depending on the spread of the fire. According to the scenarios prepared by the smoke movement on the wide glass surface façades which are frequently preferred in energy-efficient fronts, if the hot smoke moves toward the outer layer, the outer glass panel may crack and even break with high heat and pressure. The fire incidents in this context make it necessary to take precautions on fire safety in energy-efficient façade design and application stages in terms of ensuring the safety of life and reducing the financial losses [2].

#### 2. Single-layer façade systems

Façade systems have started to change with the development of building materials, namely, iron steel and concrete, starting from the nineteenth century. Building shell is an element that provides the distinction between inner and outer spaces which is made by primitive methods in the pre-industrial period. After the industrial revolution, the building shell became a bearer. In this case, due to the widespread use of iron materials, frame systems consisting of a combination of linear elements which cause the architecture have also enabled the formation of two separate systems, the structure and the shell. The double/single shell facade systems developed as a result of these developments reduce the energy consumption of the building. However, the air flow between the floors during the fire (flue effect), and the nature of the materials used for insulation, facade geometry, and so on cause rapid spread of smoke and flame. Energy Performance of Buildings Directive includes the Energy Efficiency Law in Turkey since December 5, 2008; the guide has been put into place. The objective of this regulation is to ensure that energy and energy resources in buildings are effective and efficient, to prevent energy wastage, to reduce energy costs and to protect the environment, to save energy and to provide energy inside and/or to the environment [3]. In this context, in line with the provisions of the regulation, single-layer façade systems have been preferred especially in the existing building blocks in our country. Before the transition of the fire problems experienced in the energy-efficient façade systems to the selected sample building, the general installation system of the single-layer façades and the criteria of the national standards for possible fire problems will be examined. The installation of this façade system will be discussed in general in order to avoid mixing the façade with a single-layer façade.

#### 2.1 Single-layer façades

It can only be defined as the outer wall which carries its own load and is connected to the carrier system on each floor. Such façades are independent of the building carrier system and are non-supporting external covering systems, which are constructed on the outer surfaces of the building but which consist of elements that carry the load, acting as a two-way filter of the building's relationship with the Investigation of Energy-Efficient Façade Systems in the Context of Fire Safety DOI: http://dx.doi.org/10.5772/intechopen.87836

outside environment. Commonly used systems for such façades are given in Table 1.

Single-layer façades are the type of façade often used in building the shell. Especially with the advancement of glass technology, this demand is increasing. It has been the subject of regulations and standards that the resistance to fire can be increased if interventions are made for interior joints/floors in these systems, in the joints of the walls of the floors, and in the openings in the outdoor area and in the joint gaps made for joining the end points of the two materials. It said that the national fire regulations in Turkey are located in the following provisions related to the façade type. In July 2015, published in the Official Gazette No. 29411 and still in force "Classes of fire reaction class (including thermal insulation materials) at least A2-s1, d0 class in buildings with a height of more than 28.5 m." The obligations that come with this amendment determine the conditions for the materials and systems to be used in conventional façade systems as follows:


#### 2.2 Multilayer (double-shell) façades

Multilayer façade is a façade system consisting of a double glass shell separated by a so-called air corridor. The inner shell serves as part of a conventional wall or façade, while the outer shell, usually made of a single glass, forms a protective face against external weather and noise.

By placing solar control elements in the intermediate zone, which is located between the two glass shells and protected from the external climate, it is possible to control the solar radiation depending on the season. By opening the windows in the inner shell, the building can be naturally ventilated and cooled. With the addition of a second glass shell, the wind pressure on the inner shell surface decreases and allows window opening even at the top floor of a high building. This allows for natural ventilation and increases user comfort. Double-layer façades are generally examined in four types as classified in the following:

Building-level double-layered façades: They are not horizontal and vertical dividers in the space between the double shells, but with a continuous buffer gap running along the façade. In such façades, the desired ventilation in the intermediate space is usually provided by the openings in the ground and roof alignments.


Investigation of Energy-Efficient Façade Systems in the Context of Fire Safety DOI: http://dx.doi.org/10.5772/intechopen.87836


#### Table 1. Single-layer façades [4].

#### Figure 1.

Conditions in façade systems. (a) Conditions in façade systems connected to building heights. (b) Conditions in façade systems for adjacent buildings with different heights.

Corridor height double-layered façades: Double shell isthe most used type of façades. These façades are obtained by horizontal partitioning in the intermediate space. The air intake into the cavity is provided from the openings at the lower points of the floor slab and the air outlet from the openings at the upper points of the floor slab.

Box window type double-layer façades: These are façade systems where the space is horizontal and vertical and works as independent and small boxes.

Shaft type double-layer façades: Façade systems are used to connect the box window façade units with vertical air shafts. Double-layered façade systems in high-rise buildings are frequently preferred for reasons such as ecological, durability, clean façade appearance, and prestige. However, in the case of using double-shell curtain walls, the chimney effect between the two shells occurs faster than the flame and smoke spread on the surface of the single-layer façade. The velocity of the air taken from the lower elevation in the double-layer façades that continue along the height of the building decreases to the upper elevations as the height increases, but it is never zero.

#### 3. Method

In general, materials and systems used as the topcoat in both front systems and the matrix expansion for the dangers that may occur on the basis of the façade design are given in Table 2. In the row section of the table, energy-efficient façades are divided into two main headings: outer covering/system features and façade

features. In the column section, the hazard criteria that can be formed on energyefficient fronts are listed according to many characteristics. The level of the hazards that may occur according to the colors given below in the legend is determined by overlapping the rows and columns.

The levels of the problems that can be caused by the coating materials used in the energy-efficient façade design and the danger that can be caused by the façade systems and/or the danger that may be created according to the matrix expansion are given in Table 2. In general, the levels of the hazards encountered during the


\* FF (fire fighters), \* FD (fire departments)

Presents a low risk when unmitigated or is not applicable to the listed attributes (low or N/A). Presents a moderate risk when unmitigated (moderate). Presents a moderate risk when unmitigated (high)

#### Table 2.

Fire-induced danger associated with the façade [6].


#### Table 3.

Display of fire hazards in energy-efficient building elements [6].

fire in the energy-efficient single-layer exterior cladding and finishing systems and the face of these hazards related to the strategies regarding the measures that may limit the spread of the fire determined are given in Table 3.

In this study; the selected hospital building fire will be examined according to the matrix method given above. According to the findings to be obtained measures and recommendations to be evaluated and interpreted.

#### 4. Case study

The fact that the buildings where single-layer or double-layer façade systems are applied are generally multi-story buildings and the high number of people working and sheltering in these buildings requires that fire and safety measures in these buildings be handled more carefully. In this study, in the light of the observations, researches, and the information obtained as a result of the interviews conducted with the related persons, the fires of the façades will be pointed out. In the framework of the provisions of the regulation, fire safety will be evaluated on the fronts, and what should be related to fire safety systems will be determined.

Taksim First Aid Research and Training Hospital, Istanbul: 2018 fire data

Façade features: The façade of the fire spread is designed as a single-layer curtain wall made of a combination of aluminum composite panel and compact laminate. The exterior claddings are mechanically fixed to their own construction, and the ventilation gap between the façade cladding and the façade has been formed. XPS panels are fixed to the outer wall of the building for insulation purposes. It has been the most important factor in the growth of fire due to its flammable property which is easily ignited. The building had a fire in 2011 as well, and a mineral-based insulation material was used instead of the easily ignitable insulation material that was damaged in this fire. In other words, while some of the insulation materials of the building are mineral based, some of them remained organic based. A general view of the hospital is given in Figure 2 [7].

Fire propagation: The part of the building that is covered with organic-based insulation material has not been damaged. A block was connected with the corridor block, which when blew, the glass façade melted the steel construction, and fire moved from the openings like windows and doors on the front to the interiors, ignoring the offices, patient rooms, corridors, office equipment, medical devices, and documents, and the smoke generated by the fire adversely affected the indoor air quality of the hospital by moving up to the interior spaces which must be fully sterile, such as the operating room. Figure 3 shows the spread of the fire after the start of the fire.

The result: from the flammability of the insulating material used in the façade and from the ventilated space in the front finishing system, the fire progressed

Figure 2. General view of hospital [8].

Investigation of Energy-Efficient Façade Systems in the Context of Fire Safety DOI: http://dx.doi.org/10.5772/intechopen.87836

Figure 3. Vertical analysis of the starting point of the fire (a) [7], (b) [9].

rapidly upward. The form of the façade can make a chimney effect and caused the spread of fire [7].


\* FF (fire fighters), \* FD (fire departments)

Presents a low risk when unmitigated or is not applicable to the listed attributes (low or N/A). Presents a moderate risk when unmitigated (moderate). Presents a moderate risk when unmitigated (high)

### 5. Results

In order to determine the fire propagation and limitation strategies of the sample study and to interpret the result, the data of Table 2 and Table 3 were used. Also, other criteria that are considered in the study are added in Table 4 and Table 5. The


#### Table 5.

Display of fire hazards in energy-efficient building elements for case study.

Figure 4. Façade after fire [7].

Investigation of Energy-Efficient Façade Systems in the Context of Fire Safety DOI: http://dx.doi.org/10.5772/intechopen.87836

façade cladding systems used in the fire-exposed part of the building (glass curtain wall system, mechanically assembled aluminum composite panel, and compact laminate panel) are obliged to comply with the requirements of Turkey national fire regulation with all materials used in the façade installation (including insulation materials) which must be at least A2-s1, d0 class. In addition, when the thermal insulation system, which is formed by using heat insulation material, dowel, plaster net, plaster, and other similar equipment, is applied in the regulation, the system must be certified by an accredited laboratory within the scope of the relevant standards. System fire response report is essential. It is seen in Figure 4 that the façade design which does not satisfy these provisions causes the fire to spread rapidly.

The air gap between the chimney effect and the mechanical assembly created by the physical characteristics of the area where the fire grew created the ground for the fire to spread easily.

#### 6. Conclusion and discussion

The system, application, and materials related to the fire caused by the fire in the building are as follows:


The fire-safe design of buildings today is based on the use of existing methods and harmonized standard fire tests and codes. The purpose of these tests is to assess the fire hazards arising from building materials, products, and systems in the building. Standard tests provide ratings used to assess fire performance in the event of a fire. However, these ratings only provide information about the behavior observed for this test [10, 11]. As a result, there is a great need for the development of new validation systems for energy-efficient façade systems. Existing regulations and classification systems are not sufficient to define or represent the characteristics of modern façade systems. It is important to mention that the design of the façade system and the envelope design of buildings in general have changed significantly in the last decade. There are several large- or full-scale testing methods that can be

#### ISBS 2019 - 4th International Sustainable Buildings Symposium

used as a basis for the development of new validation methods for façades. However, they are used only for the material and system tested. Since there are uncertainties regarding the actual fire safety targets of the façades, it would be important to identify fire risks if appropriate solutions are available and to draw up analyses based on case studies on fire statistics and fire incidents. In the present practice, it is vital to make a holistic view of the energy sufficient façade fire safety assessments with uncertainties in the objectives and acceptable solutions. This is especially true for modern façade systems.

### Author details

Evser Civelek<sup>1</sup> \* and Figen Beyhan<sup>2</sup>

1 Project and Approximate Cost Department, Ministry of Defence, Ankara, Turkey

2 Department of Architecture, Gazi University, Ankara, Turkey

\*Address all correspondence to: evscivelek@gmail.com

© 2019 The Author(s). Licensee IntechOpen. This chapteris distributed underthe terms oftheCreative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Investigation of Energy-Efficient Façade Systems in the Context of Fire Safety DOI: http://dx.doi.org/10.5772/intechopen.87836

#### References

[1] Energy Efficiency Law of the Official Gazette 02 May 2007 day and 26510 decision. (In Turkish)

[2] Beyhan F. Façade systems and fire safety in contemporary architecture. BEST Building Electrical Electronic Mechanics and Control Systems. 2010; 105:196-201. (In Turkish)

[3] The Regulation on Energy Performance in Buildings Official Gazette 05 December 2008 date and 27075 decision. (In Turkish)

[4] White N, Delichatsios M. Fire hazards of exterior wall assemblies containing combustible components final report. The Fire Protection Research Foundation, Massachusetts, USA; June 2014

[5] BYKHY (Regulation on Fire Protection of Buildings). The Council of Ministers 16 March/2015 date and 2015/ 7401 Number Decision Official Gazette 09 July 2015 date and 29411 Number Publishing "Alteration". (In Turkish)

[6] Meacham B et al. Fire safety challenges of green buildings, Springer Briefs in Fire, © Fire Protection Research Foundation. 2012. DOI: 10.1007/978-1-4614-8142-3

[7] [Internet]. Available from: http://tgub.org.tr/Images/ pdf/GAZIOSMANPASA-TAKSIM-EGITIM-VE-ARASTIRMA-HASTANESI-YANGINI-RAPORU%20\_ Prof.Dr.FigenBeyhan.pdf

[8] [Internet]. Available from: https:// www.trhastane.com/gaziosmanpasataksim-egitim-ve-arastirma-hastanesi-9100.html

[9] [Internet]. Available from: https:// www.haberturk.com/ihtimallerbelli-ya-ihmaller-1909353

[10] Jensen G. Fire spread modes and performance of fire stops in vented façade constructions—Overview and standardization of test methods. In: MATEC Web of Conferences 9, Owned by the authors, published by EDP Sciences; 2013

[11] Juan PHM. Performance-based methodology for the fire safe design of insulation materials in energy efficient buildings [Ph.D thesis]. The University of Edinburgh; 2015

Chapter 64

Abstract

1. Introduction

793

(1980–2014)

Impact of Capital Flight on

Economic Growth of Nigeria

Fatima Muhammad Lawal and Arzuhan Burcu Gültekin

This chapter evaluated the impact of capital flight on economic growth of Nigeria using autoregressive distributed lag (ARDL) technique and a secondary source of data over a period of 35 years (1980–2014). The chapter also examines the causal relation between capital flight and economic growth using Granger causality test. The long run estimates of the variables using ARDL model reveals that capital flight has a negative effect on economic growth of Nigeria, while the result of the Granger causality test reveals a bi-directional causal relationship between capital flight and economic growth. Based on empirical findings, the chapter suggests the need for policies to impose the economic growth that reduces the flight of capital to an increase in economic growth. More generally, the chapter also recommends that a new overall strategy, political, and public policies should be made more stable and certain in the country. This will make investors to be rest assured about the impact of these policies/ strategies on the real value of their domestically held assets in the future and to encourage Nigerians abroad to come back home and invest in the country.

Keywords: capital flight, ARDL, economic growth, Granger causality, Nigeria

Capital flight is the outflow of huge capital in the form of money from country to country. Capital flight has frequently been regarded as the economic reaction to the portfolio choices of wealth resident of some debtor countries in recent years [1]. In the words of [2], capital flight is an unlawful movement of funds from one country to another. Certainly, it is an unusual flow of capital, as the government does not sanction it. This is because exchange of capital controls imposed by the particular country is not adhered to. Capital flight weakens sustainable development in different ways, both directly and indirectly. It drains domestic savings, depresses capital accumulation which is the key driver of long-term growth. Capital flight weakens sustainable development because it reduces government resources, thus weakening financial public infrastructure and the provision of social services. The Nigerian economy faces massive financial hemorrhage because politicians, foreign investors, and corporate bodies shift funds to foreign countries and convert from Naira to the dollar [3]. According to [4], the imperative question is the reason why capital flight from Nigeria has gained so much importance over the years. Giant capital flight from the country has been linked to a large balance of payment

#### Chapter 64
