What is modular construction? Types and key advantages explained
Modular construction has quickly evolved into a solution for both temporary and permanent structures. With constant pressure to deliver shorter builds, minimise disruption, and more, many contractors and developers are considering modular systems. As demand increases across commercial, residential, healthcare, and industrial sectors, it’s important to understand how this method of construction works.
But what is modular construction? We’ll break it down in this blog, covering the types available, how the process works, and the main benefits and challenges attached to the method.
What is modular construction?
Modular construction is the process of designing, manufacturing, and assembling buildings using pre-engineered modules in a factory. These modules are essentially volumetric units, often complete with structural framing, internal walls, building services, insulation, and finishes. Once these modules are completed, they’re transported to the site and connected to form the building.
The main difference between modular and traditional construction is that most of the work takes place in a controlled environment, like a factory. It aims to allow progress both on and off-site at the same time, supporting shorter project times.
Applications
You’ll see modular construction used in many different sectors, including:
- Offices and retail buildings
- Residential housing and apartments
- Schools, training centres, and other educational facilities
- Hospitals
- Hotels
- Industrial buildings
- Temporary site offices, welfare units, and emergency-response facilities.
Types of modular construction
We can split modular construction into two categories: permanent modular buildings (PMB) and relocatable modular buildings (RMB). Both of these share similar manufacturing principles but are designed for different purposes. Let's explore these in some more detail and learn exactly how they differ.
Permanent modular buildings
Permanent modular buildings are designed to be installed in a fixed location for the entirety of their life, and are engineered to the same structural and performance standards as conventional buildings.
There’s a variety of buildings that can fall under this category, as many are permanent structures, but it also includes long-term solutions such as healthcare facilities, multi-storey residential developments, schools, and commercial offices.
Relocatable modular buildings
Relocatable modular buildings are designed for mobility and reusability. They’re engineered to be dismantled, transported, and installed at different locations, as and when needed, making them ideal for temporary or semi-permanent applications.
Some typical uses include temporary classrooms, site accommodation, field hospitals, laboratory space, and construction compound buildings.
Modular construction processes
The modular construction process requires strong coordination between design teams, manufacturers, contractors, and site managers. Many stages might mirror those of traditional construction, but it’s often the order and overlap of these tasks that differ. Below are the main processes of modular construction in order.
1. Design
The first and one of the most critical stages of a modular project is design. This is where everybody must come together and align, including manufacturing capabilities, transport limitations, and foundation requirements. Because modules are volumetric units, decisions on dimensions, weight, materials, and connection points must be finalised earlier than they are in traditional builds.
2. Approval
Modular buildings need to comply with the same regulatory framework as conventional construction. Planning permission, building control approval, structural certification, and specialist compliance documents (e.g. fire safety documentation & structural certification) all play a part. Manufacturers often have established processes for handling approvals, making sure documentation reflects the details of modular systems.
3. Foundation preparation
Now that all the approvals are ticked off, the foundation can start to be prepared. This could involve groundworks, excavation, service trenching, installation of drainage and utilities, and the construction of pad, strip, or raft foundations. Many of the time savings come from this stage because foundation preparation can continue while the modules are being created off-site.
4. Modules created off-site
This is one of the defining characteristics of modular construction. Inside the manufacturing facility, modules are assembled with high levels of quality control. This includes frame construction, insulation, internal partitions, MEP installation (mechanical, electrical, and plumbing systems such as heating, lighting, power, water, and drainage), cladding where needed, window and door installation, and completing internal finishes.
5. Modules transported to the site
Once the modules are created, they’re transported to the site. Because of the size and weight of the modules, they’re usually carried by large vehicles and cranes. Efficient organisation is also required here, so that the modules to be installed first are the ones transported first, so work can begin promptly.
6. Installation
During installation, most of the lifting will be supported by cranes, putting the modules into place and positioning them. After this, things like structural connections, weatherproofing details, and joint sealing can be completed, and then electrical systems, plumbing, heating, ventilation, and fire protection can also be installed. When everything is installed, the final external finishes and internal touch-ups can be carried out.
Advantages of modular construction
Modular construction offers multiple advantages that appeal to clients, contractors, and design teams. Although the level of benefit depends on how complex the project is, it can deliver benefits such as improved predictability and operational efficiency.
Great flexibility
One of the major strengths of modular construction is its flexibility. Modules can be configured to create a wide range of building types, from single-storey facilities to multi-storey developments. As well as this, the buildings can be easily expanded, reconfigured, and even relocated in the future.
Speed of construction
Another one of the most important reasons why modular construction is advantageous is that projects can often be completed quickly. This is because tasks like site preparation and manufacturing can be completed at the same time, rather than waiting for the site to be ready for the builds. Delays related to the weather can also be reduced when modules are created in factories.
Cost-efficient
With the time savings to be had, modular construction methods can be cost-efficient, reducing overhead costs and more. While these savings tend to vary by sector and specification, the increased efficiency and reduced waste often result in a strong value for money.
Potential for reduced waste
Off-site manufacturing supports more efficient material use. By working in a controlled environment, manufacturers can manage inventory precisely, reduce offcuts, and recycle materials more effectively. Reduced on-site activity also means fewer opportunities for material damage or wastage.
Modular construction challenges
Modular construction also has its challenges as well as its advantages. One of the most significant needs is space when transporting modules. These units can be very large and heavy, so sites must provide sufficient access for these vehicles, including areas to turn and space for cranes if required. If the end location is in a busy urban area or somewhere that might be constrained, then there may be a few logistical difficulties that will need to be discussed in the planning stage.
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We hope this blog answers the question of ‘what is modular construction?’. Whatever your project, we have a range of products and materials fit for a range of applications, including brickwork, flooring, waterproofing & damp proofing, and more.
Don’t forget to contactour helpful team if you have any questions about our products or need support in finding the right products for the job.