Flexibility. One can continually add to a modular building, including creating high rises. When the needs alter, modular buildings can be disassembled and the modules emptied or refurbished for their next use reducing the demand for raw materials and minimizing the total amount of energy expended to make a construction to meet the new need. In essence, the entire building could be recycled in some cases.
Indoor construction. Construction is independent of weather, which can boost work efficiency and averts damaged construction material.
Modular construction permits for the construction and the site work to be performed simultaneously. According to some materials, this can reduce the total completion schedule by up to 50%. This reduces labour, financing and supervision costs. To save even more time and money, the majority of design and engineering disciplines are part of the production process. During site-built construction, walls cannot be placed until flooring are set up, and ceilings and rafters cannot be added until walls have been erected. On the flip side, with modular construction, walls, floors, ceilings, and rafters are all built at precisely the same time, and then brought together in the exact same mill to form a construction. This process can allow modular construction times of half that of conventional, stick-built construction.
Environmentally friendly building procedure. The controlled environment of the factory allows for more precise structure when permitting the extra stuff to be recycled in house. 
Low waste. With the very same programs being continuously built, the manufacturer has records of exactly what quantity of substances are needed for a given job. Together with the consistency, builders can design systems which use common lengths of timber, wallboard, etc.. cut items with maximum efficiency, or have the ability to order special lengths in bulk. While waste from a site-built dwelling may typically fill several large dumpsters, construction of a modular house creates much less waste. As stated by the UK group WRAP, up to a 90% reduction in substances can be achieved through using modular construction. Materials minimized contain: wood pallets, shrink wrap, cardboard, plasterboard, wood, bricks, concrete, and cement.
Ability to service remote locations. Especially in countries in which prospective markets may be found far from industrial facilities, such as Australia, there may be a lot higher costs to build a in-house property in a distant area or a place experiencing a construction boom such as mining cities. Modular buildings can also be beneficial in providing sanitary and medical facilities at which time, space, and money are a problem.
Modular construction can also give an edge in similar categories in the International Green Construction Code.
Quality. Mixing traditional construction methods, quality manufacturing and third party agencies that provide random inspections, testing, and certification services for quality management, commercial modular buildings are made in strict compliance with appropriate local, state, and federal regulations and codes. On account of the need to transport modules to the final site, each module has to be built to independently withstand traveling and installation prerequisites. Thus the final module-to-module assembly of independently durable elements can yield a final product which is more durable than site-built structures. Modular buildings frequently use Structural Insulated Panels (SIPs) in construction, which offer a range of advantages over traditional building materials. SIPs panels are a mild yet lasting mix of board and closed-cell polyurethane (PU) or expanded polystyrene (EPS) insulation. They are air-tight, and as such provide excellent thermal performance. They also offer superior moist and cold resistance when compared to wood and other materials, and are resistant to both compression shrinking and cold bridging.  Modular units might also be designed to match in with outside aesthetics of any present building and modular units after constructed can be almost indistinguishable from a site-built structure.
Improved Air Quality - Many of the indoor air quality issues identified in new construction result from elevated humidity levels from the framing materials. Because the modular structure is substantially finished in a factory-controlled setting using dry materials, the potential for high levels of moisture being trapped inside the new construction is removed.
Modular buildings have been argued to have advantages over conventional buildings, for a variety of factors.