A. Chocalingum
Faculty of Engineering,
University of Mauritius
Email: arassen.chocalingum@umail.uom.ac.mu
B.Y.R. Surnam*
Lecturer,
Mechanical and Production Engineering Dept.,
Faculty of Engineering,
University of Mauritius.
Email: y.surnam@uom.ac.mu
* For correspondence and reprints
This paper describes the sustainable use of constructional metals based on building design, in
Mauritius. A holistic approach is undertaken and all the aspects linked with the sustainable use of constructional metals, especially steels, are investigated. Concrete data on steel as a
21 st century constructional metal is provided. Recycling and corrosion protection of steels and the use of Eco-buildings, in Mauritius, are discussed. This was performed through the use of surveys.
It was found that steel remains the dominant constructional material in Mauritius. Recycling of metals is performed in Mauritius and corrosion protection of structures through the use of suitable coatings is common. Also, it is now that professionals, building owners and clients are putting into practice the ‘Green Building’ Policy with the first construction of an Eco-
Building at Ebene Cyber Village. Finally, other green concepts for buildings in Mauritius have been illustrated.
Keywords: Sustainability, Eco-Buildings, Constructional metals, corrosion
From the latest available data from the Central Statistical Office (2008), constructional metals are more than ever manufactured and used in Mauritius. The increasing use of metals result from the actual developments in the construction sector where there is a high demand for medium-rise and high-rise buildings. Even with the upward trend of constructional materials, in particular steel, which has been experiencing volatility in the last few years, architects and structural engineers still rely on them and it should be noted that steel still dominates the marketplace for buildings (AISC, 2009).
The two main metals that are increasingly used in Mauritius are iron and steel. The annual report of the Central Statistics Office for December 2008 shows that the number of steel tubes and structures produced locally to meet the high demand in the construction sector has increased by 22.2 thousand tones since year 2000 (CSO, 2008). These metals find their applications mainly in hospitals, bridges, buildings, hotels, covered stadiums, sport

complexes and in the port sector. Though steel is regarded as the framing material of choice for more than a century, modernism has given rise to new concerns about its effective use, performance and safety. Building Teams are more than ever tackling issues such as the efficiency, sustainability and the building’s stability under load and environmental conditions for a long term basis.
‘Steeling’ for a sustainable future is the main theme indeed for many Eco-events organised worldwide recently. A global trend that has played to the advantage of structural steel has been to drive for more environmentally friendly built works. According to some Steel
Industry Organisations, steel is the world’s most recycled constructional material (AISC,
2009; Sansom, 2007; World Steel Organisation, 2009). This fact is based on statistics available in North America – suggesting that 88% of all steel products and nearly 100% of structural steel beams and plates used in construction are recycled into new products. This makes steel a very sustainable material.
Developed countries like the U.S.A and England have sought out other solutions for building construction using lightweight metals such as the light-gauge steel. This type of steel also known as cold-formed steel is gaining strength as a robust and structural approach for buildings especially schools, hotels and industrial parks. The structural aspect of the lightgauge steel is mainly for framing purposes. In other words, it offers a substitute for wood and concrete framing. Accordingly, Todd (2007) reported that steel is winning on sustainability over concrete. As per the Steel Framing Alliance, SFA (2009), in the U.S.A, lightweight steel yields less scrap and waste and has the highest strength-to-weight ratio than any building material. Another advantage of steelwork is its ability to be taken away and be accordingly re-worked with. In other words, the different elements forming the steel work can be unbolt and dismantled for future projects like the case for the Sydney Olympic Stadium (Elliot,
2007).
‘Green buildings’ is another concept which is becoming common in the construction industry and is in line with the sustainable use of materials (Guy et al, 2007; Hackler & Holdren,
2008). Moreover, existing buildings which have been built on classical constructing materials are now being transformed to ‘Green Buildings’ – refurbishment (Kapoor, 2008). This is the case for an office at Winchester in the UK where lightweight steel frame windows have taken place of huge masses of concrete blocks as shown in Figures 1 and 2 (Lane, 2009).
Figure 1- Before refurbishment of the office

Figure 2- After refurbishment – transformed building with lightweight steel frame windows
This is indeed sustainability as the Winchester office is now classified as one the greenest offices in the UK. In other words, Green buildings do not necessarily have to be new
(Cortese, 2008).
Many studies have been undertaken worldwide in assessing Green buildings performance.
The best performing buildings in the study were those that took a fully integrated approach to sustainable design—addressing site development, water savings, energy efficiency, materials selection, and indoor environmental quality (Winstead, 2008). As a fact, Miller (2009) reported that the green building industry will grow by more than 60 percent this year, maintaining the strong growth pattern of the past three years. Also, before any such Green projects are undertaken, clients are much relying on Environmental Impact Assessment (EIA) reports from the respective consultants to model the overall project and thus analyzing how sustainable are those projects (Piercy, 2009).
The use of constructional metals is closely related to sustainable development. Recycling, corrosion protection of metals, use of new materials and construction of eco-buildings are some aspects leading to the sustainable use of materials (Watson, 2008). With the ‘ Maurice
Ile Durable ’ project, it is of utmost importance to look into these factors. The purpose and objective of this paper would therefore relate to the following issues:

The quantity of constructional metals that are produced and used in Mauritius.

An assessment on the use of constructional metals like steel in buildings and in industries.

Steel recycling in Mauritius.

The protection given to metallic structures present in severe atmospheric conditions.

Green building projects in Mauritius.

The methodology adopted for this paper includes the following:

Identification of sectors and sector categories which deals with constructional metals.

A survey research based on the use of constructional metal in Mauritius.

A survey based on the preventive measures to constructional metals, undertaken by industries against severe atmospheric conditions

Interviews with specialists in Eco-Building and Steel Industry manufacture.
Five sector categories were considered, namely:

Infrastructure

Utilities

Transport

Production and Manufacturing

Others (Include hotels)
The surveys performed were descriptive ones. Since surveys can only produce approximations but never precise measurements, the questionnaires were designed so that the respondents can give answers as close as possible to the reality, as per Hoinville et al, 1989.
As a result, the questioning techniques chosen were based on open-ended and direct questions type.
3.1 Quantity of steel produced locally
Steel is the most used manufactured metal in Mauritius (Central Statistics Office, 2008). With more than 68.2 thousand tonnes of structural steel manufactured, compared to 46.0 thousand tonnes manufactured in 2000, this net increase of 48.3% is mainly associated with the ongoing construction of medium-rise, high-rise, commercial and residential buildings round the island. The building constructions at the Ebene Cyber Village are examples for the vast use of structural steel.
3.2 Buildings and industries having constructional metals
As per the CSO’s annual report for 2008 and research work based on constructional metals
(Surnam, 2002), steel is very much used in Mauritius. All of the industries interviewed have structural steel as members. Figure 3 shows that, steel remains by far the most used constructional metal in Mauritius among which there is also stainless steel and copper. It is important also to note about the gaining in strength of aluminium in the Mauritius market.
More residential buildings and medium-rise buildings are opting for aluminised doors and windows frames rather than steel. It is a fact that a life-cycle assessment should be conducted to determine the selection of Green Materials (Amopofo-Anti, 2009; Paterson, 2009).

Number of respondents
25
20
15
10
5
0
Steel Stainless steel Copper Other
…
Figure 3- Representation of the structure Materials used by the respondents
Moreover, most of the industries surveyed have a combination of different materials used or uses only one of the materials defined. That is, apart from steel being the mostly used metals, some structures in the industries are constructed using other materials and stainless steel is one of them. In some cases, a combination of two and three materials is used as per the respondents. Figure 4 shows this representation and among 26 industries (neglecting manufacturer of coatings and plastic pipes) only one industry uses all the materials defined as per the survey questionnaire.
Materials
Other only
Steel only
Steel & Other only
Steel & Stainless steel only
Steel, Copper & Other
Steel, Stainless steel & Other
Steel , Stainless steel & Copper
All materials
0 2 4 6 8
Number of Industries
Figure 4 Representation showing the combination of materials used in the industries
From figure 4, it is quite clear about the fact that steel is the most used metal in Mauritius.
Out of 25 industries and companies interviewed, 8 of them have steel only as structures in their respective industries. The ‘Other’ tag refers to materials such as aluminium and timber.

Copper and Stainless steel though much expensive, find their applications mainly in textile plants and hotels in Mauritius. As a fact for every concrete building, there are approximately two steel buildings built, which make structural steel one of the dominant constructional material in the world today (AISC’s National Environment Report, 2009).
3.3 Recycling of steel in Mauritius
According to some global Steel Organisations and consultants in the Steel industry, structural steel contains the highest recycled content of any building material (AISC, 2009; Sustainable
Now Virtual Event, 2009). In numerical terms, structural steel contains 93.3% of recycled content. According to some steel manufacturers in Mauritius, steel is recycled in Mauritius – a very good step indeed towards sustainability. However, due to confidential and professional matters, the different respondents chose not to comment of the tonnage of steel that is recycled each year in Mauritius nor do these facts appear on the CSO’s annual reports.
3.4 Corrosion Protection attributed to constructional metal in Mauritius
Being the most used constructional metal in Mauritius, structural steel however, have limitations in regard to its exposure to severe atmospheric conditions. The corrosivity of the
Mauritian atmosphere has been explained by Surnam and Chetty (2009). As shown by the mentioned authors, a major part of the Mauritian atmosphere can be classified as Category
C3, according to ISO 9223. This implies that corrosion protection is important for steels in
Mauritius. Indeed coatings are the most used method for corrosion inhibition. Most of the industries prefer sacrificial (hot dipped galvanising) or metallic coatings due to its affordable costs and availability on the local market. Organic coatings such as epoxy-based coatings are mostly used in aggressive environmental conditions (Baboian, 2002). Figure 5 demonstrates the use of these protections in industries based on their categories.
Companies
10
9
8
7
6
5
4
3
2
1
0
Organic
Metallic
None
Sector categories
Figure 5- The Type of Coating used in Industries based on their Sector Categories

It can be seen from Figure 5 that metallic coatings (zinc coating or hot dipped galvanising) remains by far the most used corrosion inhibiting method. However, only two companies do not use any type of coatings, These companies have opted for new methods including the use of plastics and the reconfiguration of the system (design out). Sustainability of structural steel do include protection to atmospheric corrosion. Research have shown that the negative impact of corrosion to a country is indeed enormous. In Mauritius for instance, many steel structures are under serious degradation. The serious state of the steel bridge at Rivieres-des-
Galets and ‘Le Forum’ steel building at Curepipe are indeed examples of atmospheric corrosion.
3.5 Green Buildings in Mauritius
According to Joya Bhandari, from Leadership in Energy and Environmental Design and member of the US Green Building Council, upto now only one building is being constructed on the basis of the Eco-Building Policy in Mauritius and itwould be working towards a
Building Research Establishment Environmental Assessment Method (BREEAM)
Certification. As per the mentioned respondent, this building will be the first of its kind in
Mauritius since it is constructed on the basis of Green Building. Regarding refurbishment of actual buildings in Mauritius, presently no buildings in Mauritius have been refurbished.
However, many architects and contractors are still relying on the classical mode of construction. In other words, huge concrete blocks are still dominating the layout of building designs. It should be noted that, time is a critical factor for building owners and clients. For example, the speed of building constructions at the Ebene Cyber Village is consequent. The lack of Green building projects initiatives in Mauritius may result from the contract period for construction of a particular commercial building, architects preferences in regard to building design and maybe reluctance over the payback period for a Green project for the owners of commercial buildings especially.
With the emerging Green Buildings concept worldwide, more products are sought to meet the growing challenges of sustainability. This is the case for HPS2000 from Colorcoat, a prefinished steel that is committed to sustainable construction. This type of coat which is the first of its kind to be manufactured has interesting Green features such as 100 % recyclable, lower carbon footprint and maintenance free (Bauer et al. 2007; Corus, 2009).
From the results and statistical analysis of the data, it can be confirmed that structural steel remains the most used constructional metal in Mauritius. Though of some reticence from respondents from the steel industries in Mauritius to affirm about the tonnage of steel scraps being recycled each year, it is to be noted that the initiative to recycle steel itself is a very good achievement towards sustainability.
The coatings applied on steel structures depend upon the location of these structures. The environmental factors prevailing are determinants for the degree of corrosion on metallic structures. Most of the industries surveyed reported a combination of factors to which their metallic structures (steel) or materials are exposed to.

Recycling steel in Mauritius is a well appreciated step towards sustainability of constructing metals. Even with multi-recycling, steel does not lose its quality or mass. Lightweight steel which is not manufactured in Mauritius, should be considered as another constructing steelmaterial among professionals in the Steel Industry. Its high speed manufacturing enables cost savings to the respective industries and at the same time speeding up the construction process.
There is no eco-building which has been completed in Mauritius presently. However, there is a great potential for eco-buildings to be constructed over the whole island.
Structural steel remains the dominant constructing material in Mauritius. With new manufacturing processes, the steel that is manufactured and used today is 40% stronger than the steel used just 10 years ago.
We would like to express our sincere thanks to Mrs. Joya Bhandari, LEED AP, for sharing with us useful information and facts regarding sustainability in general.
1.
AMERICAN INSTITUTE OF STEEL CONSTRUCTION (Publications) (2009).
Retrieved December 10, 2009 from http://www.aisc.org/
2.
AMOPOFO-ANTI, N.L., (2009). What role can life cycle assessment play in the selection of Green constructional materials. In Proceedings of the Sandton
Convention Centre Conference, South Africa.
3.
BABOIAN, R., (2002). NACE corrosion engineer’s reference book. 3 rd
ed. Houston:
NACE International.
4.
BAUER, M. et al., (2007). Green Building – Guide book for Sustainable Architecture.
Springer, Germany.
5.
BHANDARI, J. (2008). Ile Maurice: Promouvoir le concept de “Green Building”.
L’Express Newspaper. Retrieved 10 December 2009 from http://www.lexpress.mu/
6.
CENTRAL STATISTICS OFFICE (Publications) (2008). Retrieved December 11,
2009 from http://www.gov.mu/portal/site/cso/
7.
CHOCALINGUM, A., (2008). A Survey on the Inhibition of Atmospheric Corrosion in Mauritius. University of Mauritius, p. 1-49.

8.
CORTESE, A., (2008). Green buildings don’t have to be new. Green building ejournal 3 (5).
9.
CORUS, (2009). An Introduction to BREEAM for Pre-Finished Steel Industrial
Buildings. Oxford Brooks University, p. 1-21
10.
ELLIOT, R., (2007). Sustainable construction: The bigger picture. Building
Magazine, Nov. 2007, 24-25.
11.
GUY, D.L., et al., (2007). Green buildings and sustainable development. In proceedings of the Green building conference, South Africa.
12.
HACKLER, J. & HOLDREN, J.P. (2008). Walking the talk and walking the walk at the Woods Hole Research Centre: Design and performance of an award-winning
Green Headquarters. Journal of Green Building 3 (1), 3-13.
13.
HOINVILLE, G. et al., (1989). Survey research practice. 3 rd
ed. England: Gower
14.
KAPOOR, P., (2008). Refurbishing cities towards sustainability. In proceedings of the Green building conference, South Africa.
15.
MEPS INTERNATIONAL (Publications) (2009). Retrieved December 10, 2009 from http://www.meps.co.uk/
16.
MILLER, S.L., (2009). Green buildings trends to watch in 2009. Green building ejournal 3 (2).
17.
LANE, T. (2009). Taming the beast: Winchester’s green office refurb. Building
Magazine. Retrieved 10 December 2009 from http://www.building.co.uk
18.
NATIONAL ENVIRONMENT REPORT (2009). AISC: Sustainable Steel. Retrieved
10 December 2009 from http://www.youtube.com/watch?v=7ZNatXN9G3Y
19.
NEENOOTH, K., (2008). Investigation on the corrosion performance of tar epoxycoated tubular mild steel piles at the Mauritius Bulk Sugar Terminal Corporation.
University of Mauritius, p. 62-93.
20.
PATERSON, A.E., (2009). Sustainable development, architectural choices and aluminium. In Proceedings of the Sandton Convention Centre Conference, South
Africa.
21.
PIERCY, S., (2007). Sustainable construction: The bigger picture. Building magazine
Nov. 2007, 7-8.
22.
SANSOM, M., (2007). Steel: On a winning run. Building magazine Nov. 2007, 5-7.
23.
STEEL FRAMING ALLIANCE (Publications) (2009). Retrieved December 14, 2009 from http://www.steelframing.org/index.php

24.
SULLIVAN, C.C. & BENNETT, B.H. (2008). Steel Construction: Building with
Steel. Retrieved December http://www.redigitaleditions.com/olive/ODE/BDC/
11, 2009 from
25.
SULLIVAN, C.C. & BENNETT, B.H. (2008). Lightweight Steel Construction: Steel
Adds Value. Retrieved December 11, 2009 from http://www.redigitaleditions.com/olive/ODE/BDC/
26.
SURNAM, B.Y.R., (2002). An investigation on atmospheric corrosion inhibition on constructional metals used in Mauritius .
Mauritius Research Council, p.1-31.
27.
SURNAM, B.Y.R. & CHETTY, O.V., (2002). Investigations on Atmospheric
Corrosion of Low carbon Steel in Mauritius through Mass Loss and 2D Surface
Analysis. UoM Research Journal, Vol. 15.
28.
TODD, A., (2007). Steel: On a winning run. Building magazine Nov. 2007, 5-7.
29.
UNITED BUSINESS MEDIA (2009). Sustainable Now Virtual Event. Retrieved 7
December 2009 from http://www.ubmvirtualevents.com/sustainabilitynow/conference-programme/
30.
US GREEN BUILDING COUNCIL (2009). Intro: What LEED is. Retrieved 10
December 2009 from http://www.usgbc.org/
31.
WATSON, R., (2008). Green Building Impact Report. Green Building e-journal 3 (1).
32.
WINSTEAD, D., (2008). Assessing Green building performance. Green Building ejournal 3 (1)
33.
WORLD STEEL ORGANISATION (Publications) (2009). Retrieved December 10,
2009 from http://www.worldsteel.org/