Across the world today, more than half the population resides in urban enclaves. The world’s population is estimated to reach 6 billion by 2045. Planning for growth, infrastructure and affordable, comfortable housing for expanding populations includes many facets. With limited available space for housing, the prospect of redevelopment and renovation of existing structures takes on significant importance. Virtual building design using building information modelling (BIM) and virtual design and construction (VDC) offers constructive solutions to the challenges of spatial planning in urban zones. VDC and BIM technologies are evolving at a regular pace and VDC/BIM-related trends are expected to positively affect the design and construction of structures in the future, particularly with regard to redevelopment and renovation.
Typically, any new construction on a site that was being used previously is known as redevelopment. Redevelopment projects can range from construction on a single building to complete neighborhoods or even townships. Variant terms for redevelopment include ‘urban renewal’ or ‘urban revitalisation’. Revitalisation may involve the rehabilitation or renovation of existing structures. Therefore, redevelopment can include:
- Construction on vacant plots that were previously developed, such as an industrial site being redeveloped into a residential settlement
- Conversion of townhouses to large apartment complexes
- Adaptation of older structures to modern housing
Renovation, on the other hand, occurs when part of a building’s components are broken down or taken apart and rebuilt while leaving structural elements intact. Generally, renovation is less costly, since the structural work remains untouched. Permits are also easier to acquire compared to new construction projects. Renovation may not offer too much flexibility in construction, as general contractors are required to build within an existing framework. Also, costs may build up when old building walls present problems of decay and existing components may need to be updated to fulfil the latest building codes.
Progress in technology is advancing the process and efficiency of building design and construction. In today’s milieu, digital techniques enable the creation of a virtual world, where information can be conveyed into physical design. Some of these techniques are VDC (virtual design and construction) and Scan to BIM. VDC is defined as a visual management method that uses BIM (building information modelling) as part of construction analysis and the work process. VDC can seamlessly coordinate MEP systems, using 3D models to help engineers and MEP designers to design and create buildings with minimal errors at a faster rate. Scan to BIM involves the creation of point cloud models from the scans of structures. Surfaces are then restructured and developed into intelligent and parametric BIM models. This method of BIM virtual construction can efficiently guide renovation and redevelopment of existing structures or sites.
Some of the beneficial statistics of employing BIM technology in VDC are:
- Reducing project risks and improving outcome prediction
- Reducing clashes during construction, cutting down on last-minute design changes
- Improving project execution and output quality
The BIM process is acknowledged as a preferable method to document projects and has been found to be useful for cost estimation, quantity take-offs, scheduling, sustainability and maintenance.
Using the Scan to BIM technique involves the use of 3D laser scanning methods, such as airborne, mobile or terrestrial laser scanning, and the conversion to BIM afterward. For redevelopment purposes, for instance the rebuilding of sizeable industrial sites, urban infrastructure, roads, railway facilities or land development, the data can be gathered through airborne laser scanning or the possible use of drones. Tripods or hand-held scanners can collect data such as the indoor survey of a building. Data is received as point cloud models, which are converted into 3D BIM models loaded with information relevant to the project. BIM experts with relevant experience are required to handle these large volumes of surveyed data and point cloud models. The VDC experts deal with any errors or inconsistencies and develop accurate and intelligent 3D models.
Using VDC in construction increases productivity, facilitates communication between all stakeholders, decreases risks, errors and rework and thus reduces costs, labour and project design time. VDC also efficiently manages the challenges of MEP coordination, which were previously dealt with using hand-drawn installation drawings.
Studying live examples of redevelopment and renovation using VDC can better illustrate the possibilities.
- A 9-storey building in New York is in the process of a makeover that will make it a modern edifice. VDC will help visualise building improvements and execute design changes in real time. The use of VDC can help determine the best layouts for the different floors in 3D. It can also comprehend tenant requirements and customise layouts early in the design stage, then present them visually. Redesign upgrades can include the HVAC, telecom, electric, plumbing and fire protection systems. The new building’s 14-foot ceilings, 2 lobby entrances with lacquered wood, marble, limestone, granite and stainless steel finishes, arched windows and the luxurious details of its penthouse can all be visually represented and designed to be clash-free with VDC.
- A 1.4 million-sq.ft. mall in North Carolina was ripe for renovation. Lighter, brighter colours, additional amenities, new LED lighting and skylights, exterior entry, flooring, ceiling elements, smoke walls, food court, furniture, fixtures, equipment coordination, mall exterior and hardscape, canopy and auto door replacement were all designed with the use of VDC. The effective design process of VDC enabled the mall to function without closing during the renovation. Businesses were not disrupted, and customers were able to access the mall and its outlets without inconvenience.
So, the benefits of VDC in redevelopment and renovation can be summed up as:
- Improved efficiency in design coordination
- Early detection of potential challenges – 2D and 3D images are connected, allowing the identification of errors before they translate to construction.
- Decreased conflicts and alterations in design
- Clash detection and rework elimination
- Precise data in 3D models improve cost estimating and maintenance
- Project changes are instantly communicated to workers
These benefits of VDC affect stakeholders across the board, from the owner through to the contractor, subcontractors, architects, and engineers. The tangible results are lower costs, reduced time for project turnarounds, and also, with fewer errors in design, there is less paperwork to file in order to amend those errors, thus eliminating project delays. The impact of VDC technology for redevelopment and renovation in housing is thus potent and empowering, a sign of things to come.