By Rain and by Sunlight

Erected buildings are destroyed not only by rain and by sunlight, as stated by Firdausi, but also they are sometimes demolished before it becomes necessary and before the building life finishes. They are destroyed just to construct a new building. This is the predestined fate of many buildings in our city, which are replaced by new buildings a few decades after their construction. This state is desirable from one aspect as it leads to urban renovation and provides residential, official, or commercial buildings with higher constructional standards and safety level, but on the other hand, results in loss of materials used in the primary construction.

For years, the humans have realized that the present development method cannot be sustained. This fact was stipulated in the report of a UN commission in 1988 entitled “Growth Limitations” which states that the current trend of using resources and generating wastes and pollution will cause the growth and development of human societies to encounter serious limitations in near future.

Numerous solutions have been proposed to mitigate impact of resource limitation on development. The trio “consumption reduction, recycling, and reuse” is the most well-known solution among others.

The respective solutions have been offered as a part of general attitude toward sustainable development. One of the most crucial points taken into account in sustainable development is attention to the costs during the whole life span of buildings (including dismantling and demolition time). Unfortunately, most of our constructional projects have disregarded this substantial principle that the initial construction expenditures are not the only factor determining cost-effectiveness of buildings but also maintenance and performance expenses (including energy consumption) as well as dismantling expenses are also among the costs of the project.

Transport and disposal of wastes resulting from destruction of buildings is a highly costly operation and the municipalities annually spend large deal of their budgets on this issue. In addition, a vast area of the earth’s surface each year is consumed due to accumulation of construction wastes. This part of earth will become barren and unusable owing to presence of diverse chemicals in construction wastes, and in practice, the effective land area of our planet would shrink. To understand what damages the construction wastes inflict on the environment each year and to what extent they contribute to loss of resources, it is convenient to have a glance at statistics from Tehran City and also facts and figures from a sample project. It is necessary to know in advance that municipalities in some places around the world consider this issue in calculations of construction permit expenses and they impose lower costs on construction permits of the buildings which will produce less wastes in future during destruction and/or the buildings whose materials are recyclable.


Tehran City; any newcomer built a new house

According to Central Bank’s statistics, the total area of the permits issued for construction of building in Tehran City in year 2009 exceeded 12,128,000 m2 out of which 55% were buildings with metal skeleton and the rest 45% had concrete skeleton. Nearly 85% of these buildings have 5 floors or more, and totally, occupy an approximate area of 4,400,000 m2 of this city’s lands.

As a rough estimate, around 0.7 m3 of construction materials (steel, concrete, brick, mortar, gypsum, tile, stone, etc.) are used for each square meter of the building’s surface area. Consequently, more than 8 million m3 of construction waste will be generated from destruction of the buildings built in the respective year. Let’s assume these wastes will be piled at a thickness of 6 meters, and as a result, a space of earth’s surface with an area of 1.4 million m2 will be occupied; an area nearly equal to dimensions of Ekbatan Town and approximately 200 times larger than a standard soccer field.

In a sample project with educational land use which was studied for analyzing amount of different material consumption, it was observed that approximately 0.5 m3 of concrete, 150 kg of different steels, nearly 0.3 m3 of various bricks and pottery and around 100 kg of gypsum had been consumed per square meter of the area under construction. If the same values are extrapolated to the whole city, around 6 million m2 of concrete, 2 million tons of steel, 3.5 million m3 of bricks, and 1 million tons of gypsum have been used in this city just in 2009. Among the materials, it is only customary to recycle the steel consumed in the projects and other valuable materials which had been once supplied from irreversible resources of the earth are converted into waste and lost following end of the project.

All three solutions for optimal consumption of resources i.e. consumption reduction, recycling and reuse can be applied for improvement of the situation.

The first solution is to reduce the consumption level of resources. It shall not be forgotten that the energy amounts required for preparing bricks and producing cement and steel are very huge. In fact, cement production is among the most energy-consuming industries and one of the major causes of CO2 emission, one of the greenhouse gases responsible for global warming.

Recycling or recovery of materials is the second solution that might prevent from wastage of valuable resources of the earth and conversion of the lands surrounding the cities into construction waste cemeteries. Large portion of the materials used in the buildings are recyclable. Steel profiles can be returned to iron melting factories. Pressed bricks can be used again and variety of copper wires and tubes can be melted for future use. Building glasses can be also melted and transformed into new products. Wooden pieces can be recycled and applied for production of particle board and paper.

But recycling-based solutions are not limited to these items. Use of brick ballasts and concrete cuttings as aggregates in making new concrete has brought about successful results. Construction wastes have been also deployed extensively in road bases.

A greater leap along this path is to surpass recycling and to reuse the materials. It is achievable only when modular pieces are used in the building and if type axes exist in the skeleton construction and executive methods are implemented such that they allow easier dismantling and reestablishment of the building.

For example, use of steel skeleton structure with bolt and nut connections can lead to reuse of the beams with the same shape and dimensions in a new building after dismantling and demolition of the first building. Standardized doors and windows can be used exactly as before in a new building and even modular pieces of walls can be benefitted from in constructing walls of the new buildings. In the same manner, the stone pieces of the external view can be dismantled and used in another project if installed using dry connections.


Green Architecture Assessment: Is it a house in heavens or the tavern district?

LEED standard is one of the protocols utilized for assessing commitment of building to sustainable development, energy consumption level, and the consumed materials. It is also used for evaluation of building status through its life cheapest kamagra.

The respective standard was founded in 1993 when the members of US Green Building Committee (USGBC) figured out the necessity of a system for defining and measuring the concept of “green building” and analyzed the available criteria for this purpose. The respective committee was composed of architects, real estate brokers and agents, building owners, a legal advisor, an environment specialist, and industry representatives. The first edition of LEED standard was introduced in August 1998. At present, the third edition of the standard is in use and is applied for grading buildings based on the level of their “greenness”. Accordingly, a system exists for granting certificates to buildings depending on the score obtained by the project from different factors as outlined in the respective standard.

This grading system considers environmental factors during the whole life of the structure in order to assign the title “green building” to a construction. These factors include:

  • Site Sustainability
  • Efficient or Appropriate Use of Water
  • Energy and Atmosphere
  • Quality of Internal Space
  • Innovation in Design and Execution
  • Consumption of Resources and Materials

The building seeking for acquisition of LEED certificate shall observe the preconditions defined in each of the factors and achieve minimum score in all of them. Having received the initial score in all prerequisites, the respective project is graded based on its level of desirability. Different grades of “green building” certificates are granted to buildings based on the acquired scores.

The factors used in the respective standard are depicted as below:

  • Site Sustainability: In general, inherent effects of using lands, ecosystem, natural resources, and energy consumption of the region shall be taken into account by the team in charge of project. Hence, effects such as trespassing agricultural lands and wildlife zones, regional erosion, etc. shall be considered in different sites.


  • Appropriate Use of Water: Observing the parameters related to appropriate use of water might easily reduce water consumption up to 30% or more in constructional operations. Among the helpful measures in this respect is deployment of smart equipment and faucets and also efficient use of non-potable water.


  • Energy and Atmosphere: The energy generated by fossil fuels affects the environment and ecosystem in different ways. To have a green building, two points have superior priority: 1-Reduction of the required energy; 2-Use of cleaner energy forms


  • Quality of Internal Space: control of air pollution, adjustment of internal temperature, and control of illumination system are among the notable items in this factor.



  1. Innovation: Innovation in building design and also novel technologies which help construction and maintenance of green buildings are effective in scoring system.


  1. Materials and Resources: Selection of construction materials is very significant for a sustainable design. Items such as extraction, refinement, and transport of materials damage the environment in different manners including air and water contamination.


Reuse of the materials of existing buildings for new constructions is one of the most important strategies to mitigate construction wastes and the associated environment effects. Additionally, costs will be saved to a great extent. Another issue is identification and assessment of novel resources for selecting construction materials. Use of materials close to project site reduces the detrimental environmental impacts caused by transportation and also assists the economy of the region. Similarly, with application of easily recyclable materials, consumption of natural resources can be decreased to some extent. For instance, recyclable materials like paper, glass, plastics, and iron can be collected and stored in the workshop to be sent to suitable places for recycling.

Use of ceiling, floor, and wall materials as well as door and window elements of existing buildings or application of non-structural elements of building interiors such as internal walls and some ceiling elements in new buildings can help reduction of construction wastes.

Management of wasted construction materials and reduction of disposal amount, use of local materials (extraction, refinement, and treatment in the region), and consumption of quickly recyclable materials and application of timber in buildings are among the cases implied by LEED for better and cleaner usage of constructional materials.

Using LEED scoring system or analogous methods, the level of pollutant generation during the building life and amount of water and energy consumption and overall commitment of the building to sustainable development can be evaluated. And based on this evaluation, incentives like discount in construction permit cost and also expenses related to utility subscriptions can be considered for the buildings. This policy is aimed at encouraging owners and investors to construct green buildings.


Mrs. Sara Bagheri Karimi (Engineer)

Mrs. Taraneh Sedaghat (Engineer)

TAVAN Consulting Engineers

Tehran Office
#5,zavar St.,Mahyar St. Nelson Mandela Blvd Tehran-Iran
Postal Code: 1966945151
phone: +98 21 22047801
FAX:+98 21 22045887

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Postal Code: 91958
Phone:+98511 7237136
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