Emerging Technologies: New construction techniques for the housing segment

New construction techniques for the housing segment

The affordable housing sector has seen rapid growth in the past three years in terms of policy and regulations, incentives and schemes, and project uptake. Under the Pradhan Mantri Awas Yojana – Urban (PMAY [U]), 5.1 million houses have been sanctioned over a period of three years (June 2015 to July 2018). About 0.8 million houses have already been constructed and another 2.8 million are at different stages of construction. A similar scheme was launched for the rural segment – Pradhan Mantri Awas Yojana – Gramin (PMAY [G]). During financial year 2017-18, over 2.9 million houses were completed under the PMAY (G).

Further, the government has taken a number of new initiatives to meet the housing demand and address the affordability issues for the middle- and lower-income groups. Lending rates have declined, the period to avail of the credit-linked subsidy scheme has been extended and tax incentives have been introduced. There is also increased focus on the implementation of projects with innovative designs and technologies and new construction techniques. Many private developers are considering deploying new mass housing construction techniques such as prefabricated (prefab) and pre-engineered buildings. The industry is also deploying the latest equipment and materials for improving the durability and strength of structures.

Recent government initiatives

Sustainable and rapid construction of affordable houses definitely requires significant advances in technology coupled with innovative ways to increasingly use sustainable building materials. To this end, the government is planning to launch the Global Housing Construction Technology Challenge to attract the best available global construction technologies which would ensure the delivery of houses at competitive rates.

In fact, the Ministry of Housing and Urban Affairs (MoHUA) has already developed a number of demonstration housing projects to spread awareness about new technologies and green building materials for house construction. These houses are being built by the Building Materials and Technology Promotion Council (BMTPC), an autonomous body under the MoHUA, across different states in the country.

The primary purpose of setting up demonstration houses is to showcase emerging technologies suitable for the region. These houses will have a minimum carpet area of 30 square metres or as per prevailing guidelines of the respective states. The houses are designed keeping in view the dimensional requirements laid down in the National Building Code. These demonstration houses have already been constructed at Nellore in Andhra Pradesh and Bhubaneswar in Odisha. In addition, three projects at Lucknow in Uttar Pradesh, Bihar Sharif in Bihar and Hyderabad in Telangana are also in progress. The houses constructed as part of these projects comprise at least one habitable room, a separate kitchen, bathroom, toilet and veranda/balcony.

The government has also laid significant emphasis on the adoption of prefabricated and 3D construction technology to boost speedy, safe and sustainable construction.

Currently, around 125,000 houses in the country are being constructed using prefabrication technology, with several companies using 3D software solutions in order to make precasting and fabrication more efficient. The MoHUA is also exploring the use of 3D construction technologies for building affordable houses in 25 cities in the country.

Prefabrication technology consists of factory-manufactured components such as steel frames for structures, and panels made of wood, cement, gypsum and other materials for floors, walls, ceilings etc. It has a number of advantages over traditional technologies. For example, the need for formwork, shuttering and scaffolding is greatly reduced while using prefabrication technology. It also brings down the construction time and cost of labour and reduces wastage during construction. Quality control is also easier when using this technology.

3D printing refers to the production of physical objects layer by layer by an automated and usually computer-controlled machine. The machine is most often guided by digital 3D models. It either melts metal or powdered solids or ejects liquid or semi-liquid materials. It also has a number of advantages such as the capability to ensure accurate production based on the 3D models, ability to rapidly and inexpensively realise complex designs while working in an automated environment with little human involvement and minimising wastage. For instance, Meitra Hospital in Edakkad, Kerala, is India’s first fully prefabricated hospital. Also, a 2 million square foot prefabricated mall – Lulu Mall – is being developed in Lucknow.

  Emerging technologies in India

For mass housing projects, a number of formwork, precast, steel structure, light gauge steel structure and precast concrete systems are making their way into the country. The BMTPC has been authorised to operate a Performance Appraisal Certification Scheme (PACS) at the national level through which it will certify innovative building materials, components, products, units, elements of construction and assemblies, systems and subsystems, etc., required for mass housing. Currently, the BMTPC is identifying, evaluating and certifying innovative technologies to build faster, cost-effective and quality houses through PACS under the technology sub-mission set up under PMAY (U). Till July 2018, the BMTPC had identified and evaluated 24 emerging construction systems for mass housing.

For the construction of low-cost houses, reinforced concrete (RCC) monolithic technology has emerged as the most used. A total of 564,154 houses have been constructed or are under construction using this technology, as of July 2018. Of these, 514,374 houses have been built or are being built under PMAY (U) while the remaining 49,780 houses have been built or are being built under other schemes. Precast concrete technology, also called 3S technology, has also gained traction, becoming the second most preferred technology for the construction of low-cost houses. A total of 184,032 houses have been constructed or are under construction using 3S technology, as of July 2018.

Innovative green building materials introduced in construction

A number of green materials used for construction such as tyre veneer, straw and resin panels, flax insulation, warmcel, wooden fibre installation are also making their way into the Indian market. The green construction materials are low in embodied energy and resource footprints. These products are recyclable and have low life cycle costs. In India, the penetration of green building technologies for low-cost housing has been quite limited so far. However, with the focus on sustainable construction increasing, the demand for sustainable services is also increasing gradually. Several fiscal measures have also encouraged this. For example, the Pimpri Chinchwad Development Authority, offers a 5-10 per cent tax rebate to home buyers depending upon their Green Rating for Integrated Habitat Assessment (GRIHA). Also, Punjab is offering a rebate of 15 per cent on property tax if the building is Punjab Energy Conservation Building Code compliant.

The way forward

Given the huge demand-supply gap, the housing segment provides significant market opportunities to all stakeholders in the construction sector in the next four to five years. This is also expected to drive the demand for low-cost construction materials and technologies. The technology sub-mission under the PMAY would also facilitate the adoption of modern, innovative and green technologies and building materials for faster and better quality construction of houses. Another segment which is expected to gain traction is prefabrication technology. This technology is expected to not only reduce construction time but also build more cost-effective houses. Together these initiatives are expected to help make affordable housing a reality and ensure that construction is done in a sustainable manner and at a low cost.