Modular buildings present a variety of advantages over conventional buildings built on site.

· Cost savings: It is estimated that on average the cost savings in modular construction is 30% to 40% compared to conventional construction. This saving is mainly explained by the savings in labor and the more efficient use of the materials used. Additionally, modular construction significantly reduces the risk of budget overruns and unforeseen additional costs.

· Time: On average, modular building construction projects are completed 30% to 50% faster than conventional construction projects, thanks to the fact that prefabrication carried out off-site reduces production times. Modular construction can be a cost-effective and efficient way to meet project deadlines that would otherwise not be met due to the time it takes to build a typical structure on-site. This can be especially important for public projects such as schools, hospitals and urban infrastructure.

· Better quality: Modular building construction typically offers greater quality and customization than on-site construction. Since, on the one hand, prefabrication is carried out under controlled conditions that reduce the risk of defects. And, on the other hand, high quality materials are usually used, which allows us to achieve a final product with guaranteed quality. Modular buildings have been used for government projects and for the construction of large-scale commercial and residential buildings. The process has been refined over the years and modular construction companies have gained experience and reputation in producing high-quality buildings.

· Safety on site: Off-site manufacturing reduces the risk of accidents, since it is easier to manage operations and create a safe work environment.

· Design flexibility and greater customization: Modular buildings are designed and customized to meet the specific needs of each project. Modular construction offers great flexibility in terms of design, due to the use of modern techniques such as 3D modeling. Furthermore, modularly constructed buildings allow new modules to be added when necessary, allowing them to be disassembled, relocated and reconditioned for new uses, reducing costs, materials required and energy expended to satisfy new needs. One of the uses where design flexibility and customization take on special relevance is in the production and installation of prefabricated modular bathrooms in student residences, hospitals or hotels, because it favors the use of available space and reduces its remodeling needs.[6]​.

· Environmental benefits: Modular construction offers several advantages in terms of caring for the environment: it reduces CO emissions, because it uses prefabricated materials that reduce the use of energy and water for its production, at the same time as reducing the generation of waste, as well as environmental disturbance or contamination on the construction site. It is estimated that the reduction of waste and waste can reach up to 90% compared to conventional construction.

The construction of modular buildings has some disadvantages compared to the construction of conventional buildings.

· Transport: The construction of modular buildings can impose restrictions on the transportation of the modules to their location.[7]​ As the modules have to be transported by road, they normally cannot be too large, which can limit the size of the rooms.[8]​.

· Difficulty in financing: Some financial institutions, as well as banks and lenders, may hesitate to provide loans or credits for the construction of modular homes. Although this is something that has begun to reverse in recent years.

· Cultural rejection: There is still a cultural rejection towards modular buildings, mainly due to the lack of knowledge on the part of the general public regarding this type of construction. However, these buildings comply with the same regulations, codes and standards as traditional buildings, and the materials used in their construction are of equal or better quality than those of on-site constructions.

The materials used in the construction of modular buildings vary depending on the type of structure, its intended use and weather conditions.

The most common typical materials for the construction of modular buildings are wood, steel and concrete.[9]​ However, modular buildings can be built with a wide variety of materials. For example, modular buildings constructed with concrete modules can be used for commercial construction, while steel modules can be used for industrial and commercial buildings, and wood modules can be used for residential construction.

Furthermore, in many cases water approaches are developed that use more than one type of material.

Regarding the costs for the construction of a modular building, there are several aspects and factors that must be taken into account such as the type of materials used, the size of the structure or building to be built, the conditions of the labor, etc.

For example, in isolated or mountainous regions, transportation and transfer costs will be much higher than in flat areas.

However, typically some of the costs to consider are site preparation costs, labor costs, and module costs.

· Preparation of the land: The costs of preparing the work vary depending on the type of modular building and the conditions of the land.

· Labor costs: They depend on the type of modular building, the experience of the labor force and the efficiency of the construction process.

· Module costs: The cost of the modules depends on the type of modular building and the size of the modules.

In the case of large-scale projects, there is an economy of scale that allows the costs inherent to the project to be significantly reduced.

Financing for the construction of modular buildings can be obtained from banks, finance companies or lenders. Modular building construction is financed in the same way as other types of construction, typically with construction loans.[10]​.

The use of modular construction has been increasing in popularity since the mid-1980s. Today, it is primarily used for commercial buildings, such as office buildings, hotels, convention centers, and universities. It is also used for single-family homes, multi-family homes, such as apartments and condominiums, and for specialized buildings, such as hospitals and educational centers.

Modular construction is mainly used for commercial buildings that require high security or are very tall. Some examples of these buildings are airports, casinos, power plants, and government buildings.

While a modular building may be of the same quality as an on-site built building, there is still a reluctance among home buyers, as well as some lending institutions, to consider modular buildings the equivalent of on-site built buildings. This is despite surveys showing that most people can rarely tell a modular building from a site-built one.[11]​.

Modular buildings are increasingly offered as a viable and better alternative to conventional construction, due to the various advantages they provide, both for the residential and commercial and industrial sectors. According to a report prepared by the National Institute of Building Sciences of the United States (NIBS) in 2018, 87.62% of the people surveyed had used some modular prefabricated component in the last 12 months, and 81.63% planned to use them in the next 12 months.[12]​.

In countries like the United States and Canada, modular buildings are popular mainly due to their competitive prices. While in countries like Sweden, modular buildings represent up to 60% of new construction.

According to the consulting firm Straits Research, the global prefabricated modular construction market was valued at 137 billion dollars in 2021. And it is estimated that it will reach 271 billion dollars by 2030.[13]​.

This market will be driven by factors such as growing investment in the infrastructure sector, increasing demand for commercial and residential buildings, and attention to energy efficiency. However, the increase in the cost of labor and materials, as well as the lack of qualified labor for this type of work can hinder its growth.

Research and development of new technologies when it comes to modular building construction is advancing rapidly around the world. Modular buildings have been used for government projects and for the construction of large-scale commercial and residential buildings.

Modular construction is expected to become even more advanced in the future and will continue to be the preferred method for tall building construction. It is also predicted to be increasingly applied to the construction of bridges and roads. The process has been refined over the years and modular construction companies have gained experience and reputation in producing high-quality buildings.

Future research and development in modular construction will focus on improving modular design software (3D modeling) and developing better interconnections between modules.

Contenido

La construcción de edificios modulares sigue un proceso secuencial que está dividido en una serie de pasos básicos. Este proceso tiene como finalidad agilizar la implementación y desarrollo del proyecto, disminuir costes y garantizar la calidad y estandarización de todos los módulos.

Los edificios modulares deben cumplir en la mayoría de los países con las mismas normas, códigos y estándares de construcción que las estructuras construidas mediante la construcción tradicional in situ.

El proceso suele iniciar con la ideación y desarrollo de los bocetos básicos, para posteriormente realizar el análisis de costes y la planificación del calendario.

El proceso de construcción que siguen los fabricantes de edificios modulares puede variar de acuerdo con el tipo de construcción y los requisitos particulares de cada proyecto. Sin embargo, suele haber tres etapas básicas en el proceso de construcción y montaje de cualquier edificio modular: fabricación, envío y montaje y emplazamiento.

Asimismo, existen pasos previos al montaje y conexión de los módulos como la preparación de la obra, donde se disponen todos los materiales y equipos para la construcción que su utilizarán y se prepara el emplazamiento para la construcción de la edificación modular. Por otro lado, se debe realizar una cimentación. Éstos deben estar diseñados para soportar el peso de la construcción modular. Pueden ser de hormigón, acero o madera. Y pueden apoyarse en una losa, en pilotes "Pilote (cimentación)") o estar empotrados en el suelo.

El trabajo en la obra suele ser reducido, pudiendo tomar el montaje y ensamblaje de los módulos desde algunas horas hasta varios días, dependiendo del tipo y las características del proyecto.

Site selection

It is essential to select a site for modular construction. The site must be free of obstacles, have adequate access and be free of ground conditions that could cause instability. It must also have public and transportation services, including an access road to the construction site. The site must be evaluated to ensure that it is suitable for the type of modular building to be constructed.

Meteorological conditions

The meteorological conditions of the work are another important factor for the construction of a modular building. Precipitation, strong winds, temperature and humidity can affect the construction of a modular building. Weather conditions must be monitored and appropriate measures must be taken to protect the work and the building.

Modular buildings present a variety of advantages over conventional buildings built on site.

· Cost savings: It is estimated that on average the cost savings in modular construction is 30% to 40% compared to conventional construction. This saving is mainly explained by the savings in labor and the more efficient use of the materials used. Additionally, modular construction significantly reduces the risk of budget overruns and unforeseen additional costs.

· Time: On average, modular building construction projects are completed 30% to 50% faster than conventional construction projects, thanks to the fact that prefabrication carried out off-site reduces production times. Modular construction can be a cost-effective and efficient way to meet project deadlines that would otherwise not be met due to the time it takes to build a typical structure on-site. This can be especially important for public projects such as schools, hospitals and urban infrastructure.

· Better quality: Modular building construction typically offers greater quality and customization than on-site construction. Since, on the one hand, prefabrication is carried out under controlled conditions that reduce the risk of defects. And, on the other hand, high quality materials are usually used, which allows us to achieve a final product with guaranteed quality. Modular buildings have been used for government projects and for the construction of large-scale commercial and residential buildings. The process has been refined over the years and modular construction companies have gained experience and reputation in producing high-quality buildings.

· Safety on site: Off-site manufacturing reduces the risk of accidents, since it is easier to manage operations and create a safe work environment.

· Design flexibility and greater customization: Modular buildings are designed and customized to meet the specific needs of each project. Modular construction offers great flexibility in terms of design, due to the use of modern techniques such as 3D modeling. Furthermore, modularly constructed buildings allow new modules to be added when necessary, allowing them to be disassembled, relocated and reconditioned for new uses, reducing costs, materials required and energy expended to satisfy new needs. One of the uses where design flexibility and customization take on special relevance is in the production and installation of prefabricated modular bathrooms in student residences, hospitals or hotels, because it favors the use of available space and reduces its remodeling needs.[6]​.

· Environmental benefits: Modular construction offers several advantages in terms of caring for the environment: it reduces CO emissions, because it uses prefabricated materials that reduce the use of energy and water for its production, at the same time as reducing the generation of waste, as well as environmental disturbance or contamination on the construction site. It is estimated that the reduction of waste and waste can reach up to 90% compared to conventional construction.

The construction of modular buildings has some disadvantages compared to the construction of conventional buildings.

· Transport: The construction of modular buildings can impose restrictions on the transportation of the modules to their location.[7]​ As the modules have to be transported by road, they normally cannot be too large, which can limit the size of the rooms.[8]​.

· Difficulty in financing: Some financial institutions, as well as banks and lenders, may hesitate to provide loans or credits for the construction of modular homes. Although this is something that has begun to reverse in recent years.

· Cultural rejection: There is still a cultural rejection towards modular buildings, mainly due to the lack of knowledge on the part of the general public regarding this type of construction. However, these buildings comply with the same regulations, codes and standards as traditional buildings, and the materials used in their construction are of equal or better quality than those of on-site constructions.

The materials used in the construction of modular buildings vary depending on the type of structure, its intended use and weather conditions.

The most common typical materials for the construction of modular buildings are wood, steel and concrete.[9]​ However, modular buildings can be built with a wide variety of materials. For example, modular buildings constructed with concrete modules can be used for commercial construction, while steel modules can be used for industrial and commercial buildings, and wood modules can be used for residential construction.

Furthermore, in many cases water approaches are developed that use more than one type of material.

Regarding the costs for the construction of a modular building, there are several aspects and factors that must be taken into account such as the type of materials used, the size of the structure or building to be built, the conditions of the labor, etc.

For example, in isolated or mountainous regions, transportation and transfer costs will be much higher than in flat areas.

However, typically some of the costs to consider are site preparation costs, labor costs, and module costs.

· Preparation of the land: The costs of preparing the work vary depending on the type of modular building and the conditions of the land.

· Labor costs: They depend on the type of modular building, the experience of the labor force and the efficiency of the construction process.

· Module costs: The cost of the modules depends on the type of modular building and the size of the modules.

In the case of large-scale projects, there is an economy of scale that allows the costs inherent to the project to be significantly reduced.

Financing for the construction of modular buildings can be obtained from banks, finance companies or lenders. Modular building construction is financed in the same way as other types of construction, typically with construction loans.[10]​.

The use of modular construction has been increasing in popularity since the mid-1980s. Today, it is primarily used for commercial buildings, such as office buildings, hotels, convention centers, and universities. It is also used for single-family homes, multi-family homes, such as apartments and condominiums, and for specialized buildings, such as hospitals and educational centers.

Modular construction is mainly used for commercial buildings that require high security or are very tall. Some examples of these buildings are airports, casinos, power plants, and government buildings.

While a modular building may be of the same quality as an on-site built building, there is still a reluctance among home buyers, as well as some lending institutions, to consider modular buildings the equivalent of on-site built buildings. This is despite surveys showing that most people can rarely tell a modular building from a site-built one.[11]​.

Modular buildings are increasingly offered as a viable and better alternative to conventional construction, due to the various advantages they provide, both for the residential and commercial and industrial sectors. According to a report prepared by the National Institute of Building Sciences of the United States (NIBS) in 2018, 87.62% of the people surveyed had used some modular prefabricated component in the last 12 months, and 81.63% planned to use them in the next 12 months.[12]​.

In countries like the United States and Canada, modular buildings are popular mainly due to their competitive prices. While in countries like Sweden, modular buildings represent up to 60% of new construction.

According to the consulting firm Straits Research, the global prefabricated modular construction market was valued at 137 billion dollars in 2021. And it is estimated that it will reach 271 billion dollars by 2030.[13]​.

This market will be driven by factors such as growing investment in the infrastructure sector, increasing demand for commercial and residential buildings, and attention to energy efficiency. However, the increase in the cost of labor and materials, as well as the lack of qualified labor for this type of work can hinder its growth.

Research and development of new technologies when it comes to modular building construction is advancing rapidly around the world. Modular buildings have been used for government projects and for the construction of large-scale commercial and residential buildings.

Modular construction is expected to become even more advanced in the future and will continue to be the preferred method for tall building construction. It is also predicted to be increasingly applied to the construction of bridges and roads. The process has been refined over the years and modular construction companies have gained experience and reputation in producing high-quality buildings.

Future research and development in modular construction will focus on improving modular design software (3D modeling) and developing better interconnections between modules.