In order to achieve the city’s goal of being one of the most sustainable cities in the world – as well as a great place to live and work – every aspect of the city’s urban planning and architecture was approached with sustainability in mind.
Masdar City in selecting construction materials, wanted to show that major environmental savings can be made without any additional cost. For example, many already know that steel reinforcing bar, more commonly known as rebar, serves as the unseen support structure for countless number of construction projects in the UAE. From high-rise office buildings to bridges to highways, rebar is an integral component in concrete structures providing strength, flexibility and durability.
Increasingly, however, rebar is becoming known as one of the more ‘green’ materials in use today. Rebar lays claim to this title because the vast majority of rebar is produced from recycled metal, and, rebar itself is completely recyclable. In the building of the Masdar Institute buildings our specifications called for rebar composed of 95% recycled steel.
We made it a condition that contractors obtain documentation from their suppliers showing the post-consumer and pre-consumer recycled content, and asked them to document whether the steel was made in an electric arc furnace (EAF).
An Electric arc furnace (EAF) is used to melt scrap iron and steel into new steel. These plants being located close to sources of scrap material. Because EAFs use scrap almost exclusively, their products have very high levels of recycled content.
The scrap used to make the rebar is a mix of internally generated waste and scrap purchased from other factories or from scrap yards. The home scrap is a mix of “runaround scrap” generated in the production process, which does not count as recycled material, and scrap from other internal operations, which does.
Estidama credits are available if the building can be constructed with recycled and regional materials. As reinforcing steel is often made of recycled steel, it can contribute to these possible credits.
In the case of reinforcing steel, the fabricator is the final manufacturer as steel bars are modified and formed to the required shape at fabrication stage. If the fabrication is done within 500miles of the construction site the reinforcing steel price can be included in the regional material credit.
Using recycled steel also helped us to achieve our recycled and embodied carbon key performance indicators and make our planet a better place to live for our future generations.