The Complete Guide To How Modular Buildings Are Constructed

Modular buildings are revolutionizing the way building construction is done. Especially now that traditional construction seems to have hit its ceiling, modular construction is set to take building to the next level.

This is especially key for a construction industry that has seen productivity growth of only about 1% a year in the last two decades. Meanwhile, other industries are raking in higher increase, using technology to grow rapidly. Because of this, traditional construction has remained largely inefficient. Fully 57% of its activities are wasteful, leading to higher cost and no added value.

The allure of modular building is more than just the new, exotic feel of constructing buildings. Modular construction uses the same materials, and is designed to the same codes and standards as traditional construction but turns out buildings in about half the time. And often, at much lower cost.

Even better, the unique applications of technology and controlled plant building used in modular construction allow a never-before-seen freedom in home construction. These days, you can truly buck the trend and go bespoke with modular buildings, way easier than you could with traditional construction.

Considering all the benefits of modular buildings, it’s no surprise that you are interested in how the process will go. So, to help you, we made this complete guide to the construction of modular buildings so you’ll know exactly what to expect in the process.

Types of modular building construction

While all modular construction involves a process where the building is largely constructed off-site and under factory conditions, they still differ in terms of their purpose.

To this end, there are two basic types of modular building construction. They are relocatable buildings (RB) and permanent modular construction (PMC).

Relocatable building

Most of the reputation that modular buildings have as temporary buildings comes from relocatable buildings. They are partially or completely assembled building modules that are designed for multiple use.

This means that they can be used in one place, then removed from there and used elsewhere as needed. Modules of this nature include construction site offices, medical clinics, sales centers and pretty much any type of building that meets a temporary space need.

The fact that these buildings are relocatable does not mean they’re “cheap” or “flimsy” either. All relocatable buildings are designed and built to code. They are just as strong as buildings erected on-site but with the added advantage of fast delivery, easy relocation and wonderful flexibility.

Permanent modular construction

Permanent modular construction (PMC) constitutes the next phase of the development of modular construction. It is with PMC that modular construction is now challenging the space of traditional construction.

Contrary to relocatable buildings, PMC involves the creation of innovative modular building that is meant to stay in one site. It delivers sustainable construction using a method that involves prefabrication of buildings in deliverable modules.

As such, PMC enables the use of modules to construct a building project “piecemeal”, module by module. When the construction is done, the result looks just like any other house or office on the street, only with the distinction that it’ll seem to have sprung up in the night!

They are virtually the same with traditionally constructed buildings. However, they use more sustainable “green” materials, allow for more innovative solutions and provide limitless design opportunities.

What materials are used in modular building construction?

Unlike traditional construction, modular buildings are not so heavy on brick and mortar. For one, those kind of buildings are energy inefficient. Apart from that, those materials can be a tad difficult to use as they’ll make the modules several tons heavier and harder to deliver. This begs the question: what are modular buildings constructed of?

There are two major framing types used in modular construction. Instead of brick and mortar, modular buildings use either a standard wood-frame construction made of lumber or steel and concrete. Both have their unique uses although, steel and concrete are generally stronger and less combustible.

Apart from these, modular construction uses many other materials, especially as the modules come with full interior finish. The materials include

  • Acoustical ceiling
  • Drywall or VCG (vinyl covered gypsum) interior wall finish
  • CPVC, pex, or copper piping/tubing
  • Wood trusses used for roofing
  • VCT (vinyl composite tiles) or ceramic tiles

The process of modular building construction

The modular building process is similar to traditional construction in some respects but markedly different in others. Here’s what the process entails:

Stage 1: Design / engineering

All building starts with visualizing and modular construction is no different. At this stage, a lot of planning and designing goes on, with client and manufacturer coming together dream a treat.

The flexibility and innovation of modular buildings can best be appreciated at this point. This is because the whole building is highly customizable in terms of exterior as well as interior finish.

Stage 2: Design approval

At the second stage, all appropriate permits and design approvals will be sought and obtained. In this wise, modular building progresses just the same as traditional construction.

All approvals and permits are delivered with the expectation that the modular buildings will turn out just as sturdy as their traditional counterparts. And they do too, every single time.

Stage 3: Preparation of the foundation

After securing all necessary approvals, the next stage will involve preparation of the site foundation. This has to be done on-site of course, since the modules will need a sturdy foundation to sit on.

There are two types of foundations that are generally used in this wise. They are the on-grade foundation and the raised foundation.

The on-grade foundation is usually used for PMC. It is created by pouring a foundation around the proposed building perimeter. Just like traditional construction, a basement will be created this way. However, the difference is that some preparation will be made for the installation of modules when they begin to arrive.

The raised foundation can be used for temporary buildings or PMC. This foundation uses concrete piers / blocks instead of poured concrete. It will utilize a blocking plan that shows where to place blocks and how much load each will support.

The activities that will be undertaken during foundation preparation include the following:

  • Excavation
  • Grading
  • Site drainage
  • Foundation construction
  • Utility installation

Stage 3: Construction of modules at the plant

Now, this is where modular construction totally deviates from, traditional construction. At the same time that foundation preparation is going on at the construction site, construction of building modules will commence at the plant.

During this stage, the individual modules of the building will be constructed in a controlled factory setting, using an assembly line process. By using an assembly line process, each team of engineers can specialize in only one part of the process, meaning that each module can be completed swiftly.

The process will usually begin with building the module frame, ending with the interior and exterior finish. So, what you’ll have at the end of the process is a section of the building that is more than 95% complete, almost ready to move into.

The activities that will be carried out during this stage include the following:

  • Framing and floors
  • Attaching the walls
  • Installing the roof
  • Plumbing, electrical and flooring
  • Interior and exterior finish

Stage 4: Transportation of modules to site

As soon as the foundation and all on-site preparation is complete, transportation of modules to the site will begin. The modules will generally be transported using heavy vehicles and cranes.

The delivery of modules is usually staged in a way that ensures final assembly will be smooth and efficient. As such, the modules will be shipped in the order that they are meant to be installed. So work begins immediately.

For the purpose of transportation of modules, it may be necessary to make adjustments to your site, especially in terms of access. All of this will have been completed during site preparation.

Stage 5: Installation of modular units

By the time installation of modules commences, traditional construction will just be about done with the foundation, and that’s hoping there were no weather or vandalism delays.

Installation of modules will be done using cranes that will lift individual modules and place them on the prepared foundation. In installation, each module is designed to fit perfectly with the next, either end to end or stacked. So there’s no delay from figuring out how to make them fit.

Once each module is on the foundation, the individual components will be seamed together. Utility connections will be made, interior finish smoothed out and exterior additions like decks, ramps or stairs, added.

Installation will continue in this manner, module by module, until the entire building is complete.

Stage 6: Site restoration

Once all installation is complete, your building is virtually ready. All that would remain is restoration of the building site. So, at this stage, the site is restored. If there is any concrete, asphalt or landscaping that was disturbed during construction, all will be repaired.

And then, it will be time to move in. If traditional construction moves smoothly, construction of the frame should be complete by now, with preparations moving towards interior and exterior finish.

So there you have it. Your complete guide to construction of modular buildings. Now that you know all about what the process entails, you’ll probably have questions like: what are the kinds of designs you can do with modular buildings or wat materials can you use for your own building.

It’s great that you have questions and we’d like nothing better than to listen and answer right back. All you have to do is get in touch with us through 01302 759447 or our email at and we will give you a shout.

And if you’d like to skip all the questions and get right down to how we can make modular buildings work for you, you can request a quote here. So get in touch and let us start a conversation.