Dilip Sharma works with Voltas Limited – a firm that has executed many retrofit projects across various segments such as oil and gas at onshore and offshore locations, commercial buildings, and central plant modifications. Some of these projects were for clients like Musanada, ADNOC, AADC, government buildings, universities, various private building owners, corporate offices, and warehouses. Sharma, regional general manager, International Operations Business Group, Voltas Limited, says: “Retrofit capability forms an integral part of our facility management vertical.”
It is therefore enlightening to hear from Sharma some of the aspects of retrofitting in the MEP sector. He says that over a period of time electro-mechanical systems and equipment become obsolete in its technology, or loses efficiency due to wear and tear, and poor maintenance. He says: “Retrofitting of existing buildings offers significant opportunities for improving its utilities performance, especially with regards to MEP systems. Certain aspects of the retrofitting are improved energy efficiency, increased staff productivity, reduced maintenance costs and better thermal comfort.”
Sharma says that before retrofitting is carried out an initial survey is needed to understand the building operational problems and the main concerns of the occupants. Thereafter, building owners appoint an experienced Energy Services Company (ESCO) to take on the responsibility for planning and implementing the building retrofit. He adds: “The effectiveness of a retrofit project is dependent on building-specific information such as geographic location, building type, size, age, occupancy schedule, operation and maintenance, energy sources, utility rate structure, building fabric, and services systems. Some of the corporations undertake retrofit programs to meet the legal requirements on environmental aspects, like phasing out of HCFC refrigerants. “The extent of the building retrofit program depends on the project objective. Generally, load bearing walls, retaining walls, load bearing columns, soffit walls, should not be broken, or else we run the risk of accidents in the building. However, partition walls, flooring and false ceiling can be broken and reworked on.”
On some cases, shallow retrofits can suffice. Shallow retrofit is used when small changes are enough towards meeting the objectives. Sharma explains: “When the asset in the building is working fine then there is no point in replacing that, or else the payback period becomes high. Normally, the life of shallow retrofits is 5 to 7 years.
“With the rapid developments in renewables and MEP products’ technology, renovation cycles are getting shorter, which allows for shallow retrofits even in modern buildings. We are down from 10 years to five years because of market pressure and technological advancements. Unless the disruption in technology makes the whole system obsolete and costly, deep retrofits may not be economically viable.”
According to Sharma, some of the design aspects to be considered when planning retrofitting include original building design, surrounding areas, underground services disruption, shutdown requirements and planning of rental utilities equipment, suitability of existing electrical loads, indoor air quality requirements, additional HVAC loads, water consumption pattern, energy savings target, regulatory environmental norms, and any other client requirements specific to the intended application or program objective. Careful selection of materials and new equipment becomes critical to meeting the program objectives. He says: “The major challenge in such programs is availability of as-built drawings and asset lists, especially in older buildings. One must never ignore the original design basis of the building or its systems. Ignorance leads to surprises during execution.”
The other aspect is managing retrofitting in a live environment. Sharma says that most of the retrofit programmes are designed to be executed in parts, where a portion of the building is isolated while rest of the building remains operational, and the programme gets completed over an extended period of time as compared to a fresh build.
He says: “Managing refurbishments in a live environment poses various unique challenges like safety, partial load shutdowns, construction waste disposal and hygiene maintenance, access issues for the rest of the tenants, noise etc. Project management team should be experienced and equipped to safely and effectively manage complex refurbishment work schedules and location to ensure minimal disruption to a client’s normal operation. If the span is horizontal it can be done section by section, but if the span is vertical then we need to do it floor-wise and as per the advice of the client. Proper signages and thorough implementation of HSE measures help in avoiding any incidence or accident at site. Awareness programs to building occupants generally help in managing the program efficiently through their cooperation.”
Products and innovation
The building retrofit challenge is to determine, implement and apply the most cost-effective retrofit technologies to achieve enhanced energy performance while maintaining satisfactory service levels and acceptable indoor thermal comfort, under a given set of operating constraints. By using appropriate energy models, economic analysis tools and risk assessment methods, the performance of a range of retrofit alternatives can be assessed quantitatively, Sharma says. The retrofit alternatives can then be prioritised based on the relevant energy-related and non-energy-related factors. Sharma adds that with the advent of technology and new product introductions in the MEP space, there are various smart products and solutions available to choose from such as smart LED lights and motion sensors; air curtains and FAHU; energy efficient AHU, FCU or split units; insulations with high reflectance and low U value; indoor air quality improvements; optimum design of building fabric; water usage reduction through the use of low flow fixtures, sensors, waterless urinals and low flush WCs; enabling building owners to install photovoltaic panels on rooftops to generate electricity from solar power; and re-commissioning of MEP systems to increase its efficiency.
Sharma says: “Retrofit technologies range from the use of energy efficient equipment, advanced controls and renewable energy systems to the changes of energy consumption patterns, and the application of advanced heating and cooling technologies. Retrofit measures should be considered in their order of economic payback, complexity and ease of implementation.”
Though MEP systems form major part of building retrofit programs, most of the contracts are generally given to civil contractors, and MEP contractors are appointed on sub-contract basis, especially in commercial and residential buildings. Sharma says: “The major challenge that MEP contractors face during the retrofit project execution is sequencing of works and access issues for MEP installations. A civil contractor’s work is relatively low-skilled work as compared to MEP systems, but due to limited knowledge on MEP systems construction, the main contractor does not appreciate the challenges faced by the sub-contractor, and becomes unreasonable at times on granting the required durations for MEP systems’ installations.
“Another big challenge faced during execution is labour productivity and idling of labour due to disruptive nature of the works. The best way to minimise this is to estimate man-months instead of man-hours for the activities involved. If labour productivity and work access issues are not managed well in close coordination with the main contractor, it may lead to huge cost overruns and poor quality of works. Apart from these construction issues, it is very important to design the MEP systems retrofit carefully to match the application requirements.”
Defining the scope of works clearly is paramount for contractors undertaking the retrofit projects, as there are unknown issues in the buildings and surroundings when it is opened up for refurbishment works. “One must estimate and plan for these contingencies during execution,” Sharma says.
He concludes by saying that since energy efficiency is gaining momentum in the region, and government authorities have pushed initiatives by defining the regulations, there is a need for good retrofit contractors with sound technical expertise in MEP systems. He says: “Today, we have many contractors claiming to be an ESCO player but the knowledge levels are still in infancy, and this would have a bearing on the rate of change, or adoption of retrofit technology within the GCC.”