Quality. Mixing traditional construction methods, quality manufacturing and third party agencies who provide random inspections, testing, and certification services for quality management, commercial modular buildings are made in strict accordance with appropriate local, state, and federal regulations and codes. Due to the requirement to transport modules to the final website, each module has to be built to independently withstand travel and installation prerequisites. Thus the final module-to-module meeting 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 provide a range of benefits over traditional construction materials. SIPs panels are a mild yet durable combination of board and closed-cell polyurethane (PU) or expanded polystyrene (EPS) insulation. They're air-tight, and as such provide excellent thermal performance. They also provide superior damp and cold resistance when compared to wood and other substances, and are immune to both compression shrinking and cold bridging.  Modular units might also be made to fit in with external aesthetics of any present construction and modular units once constructed can be almost indistinguishable from a site-built structure.
Modular construction can also give an advantage in similar classes from the International Green Construction Code.
Indoor construction. Construction is different from weather, which can increase work efficiency and avoids damaged construction material.
Ability to service remote locations. Particularly in countries in which potential markets may be found far from industrial centers, such as Australia, there may be a lot higher prices to construct a site-built house in a remote area or a place experiencing a construction boom like mining towns. Modular buildings can also be beneficial in providing sanitary and medical facilities at which space, time, and money are an issue.
Modular buildings are argued to have benefits over conventional buildings, for many different reasons.
Environmentally friendly building process. The controlled environment of the factory allows for more accurate construction when allowing the additional materials to be recycled in house. 
Flexibility. One can continually add to your modular construction, including creating high rises. When the needs alter, modular buildings can be disassembled and the modules relocated or refurbished for their next usage reducing the demand for raw materials and minimizing the total amount of energy expended to create a building to meet the new demand. In essence, the whole building can be recycled in some instances.
Low waste. With the very same plans being continuously built, the manufacturer has records of precisely what amount of materials are necessary for a given job. With the consistency, most builders can design systems which use common lengths of lumber, wallboard, etc., cut items with maximum efficiency, or be able to order special spans in bulk. While squander from a site-built residence may generally fill several large dumpsters, building of a modular dwelling generates much less waste. As stated by the UK group WRAP, up to a 90% decrease in materials can be accomplished via using modular construction. Materials minimized include: timber pallets, shrink wrap, cardboard, plasterboard, wood, bricks, concrete, and cement.
Modular construction permits for the construction and the site work to be performed concurrently. According to some substances, this can decrease the total completion schedule by as much as 50%. This also reduces labor, financing and oversight costs. To save time and money, nearly all design and engineering disciplines are part of the manufacturing process. Also unique to modular structure is the ability to simultaneously construct a building's floors, ceilings, walls, rafters, and roofs. During site-built construction, walls cannot be placed until flooring are in position, and ceilings and rafters can't be added until walls are erected. On the flip side, with modular construction, walls, floors, ceilings, and rafters are all built at the same time, and then brought together in the exact same mill to form a building. This process can enable modular construction times of half that of conventional, stick-built construction.
Improved Air Quality - A lot of the indoor air quality problems identified in new construction result from high humidity levels from the framing materials. Since the modular structure is substantially completed in a factory-controlled setting using dry materials, the prospect of high levels of moisture being trapped in the new construction is removed.