Modular Buildings versus Rigid Frame Construction

Which building system is right for your project?

As you navigate the metal building market, you’ll find a confusing web of construction methods, steel structure terms and suggestions for what type of building best suits your needs. That’s because technology and engineering are in a constant state of progression, working to improve the versatility, structural integrity and safety of large structures around the world. Let’s take a deeper look at two common types of steel structures that are each valuable but differ in construction and function: modular buildings and rigid frame buildings.

Modular Building Prices vs. Rigid Building Prices

Most consumers start their search for a new structure by asking: How much does a metal building cost? While there are numerous other factors to consider in a search for steel building kits, pricing can quickly steer you towards one building type or another.

Which Building is Which May Surprise You

By doing a quick search for metal building prices you can find countless construction methods, one of which is a modular building on eBay. While we don’t recommend eBay metal buildings, we will use their pricing to compare steel building and a building purchased through General Steel.

Building TypeBuilding SizePrice Per Square FootBase Building Price
Building A24’x48’$36 per sqft$41,472
Building B24’x48’$8-$12 per sqft$9,216-$13,824*

The Answer

We recommend reading the rest of this article to discover which building type is the right choice for your project, but you can click the link below if you can’t wait to see which has the lower cost per square foot.

Building A and B Answer →

Stacked Modular BuildingsModular Buildings

A modular building is a pre-engineered steel structure, which means its components, or modules, are built in a factory setting according to the same codes as any traditionally constructed buildings. The finished modules are transported by commercial trucks to a construction site, where they are assembled by a builder. Each module is installed to form a self-supporting structure that can support another modular unit on top. While this can be an advantage for compartmentalized vertical construction, modular buildings have limits when it comes to large-scale facilities. This becomes especially true for buildings that span wider than a semi-truck bed.

How Modular Buildings Differ from Portable Buildings

It’s important to note that while individual modules are transported from the factory to the construction site, completed modular buildings are not the same as portable buildings. Portable buildings are often used by schools dealing with limited budgets and reduced classroom space due to overcrowding. Modular buildings on the other hand, are permanent structures that are installed on a foundation and provide the protection from the elements that steel structures are known for.

Modular Construction Example

Modular Building Prices for Schools

Photo Credit: Triumph Modular

Portable Buildings Example

Portable Buildings for Schools

Benefits of Modular Buildings

One of the primary benefits of modular construction is time savings. Modular buildings are produced offsite using methods similar to the traditional assembly line, which contribute to a more efficient and focused construction timeline. As the modules are constructed separately by the manufacturer, the construction site can be assessed and prepared. When the modules are delivered to the site, about 80% of the construction is already completed. It is then only a matter of installing the modules and putting on the final touches such as utilities. When compared to traditional construction methods including site-built, wood frame construction, modular construction offers a quicker and more efficient route to the time of occupancy. The shorter construction timeline also means fewer labor costs, site disruptions, weather delays and decreased risks of on-site accidents and injuries.

Where Are Modular Buildings Being Used?

Modular buildings are common solutions for buildings that have a replicated structure. This structure would include dormitories, mid-size hotels, apartment complexes or other housing projects that have smaller units. The size of the individual modules are limited by state transportation laws since they are transported and delivered by commercial trucks. Modular buildings are able to be easily modified, making them also popular options for small additions including school cafeterias, permanent classrooms and weight rooms, among others.

Pros and Cons Recap: Modular Buildings
Shorter construction timelinesSizes are limited by transportation laws
Reduced on-site construction costsCustomization possibilities are limited
Good for replicated vertical structuresNot good for warehouses and other wide building types

Rigid Frame Buildings

Rigid frame buildings are characterized by their I-beam main frames. This framing style has produced prefab metal buildings and even highrises in its wake. In either case, these frames, located at the each end of the building and sometimes at intervals between, endure most of the building’s load. These types of buildings have become more popular as individuals, engineers, architects and companies recognize the strength of the structure and potential for creative design. The word “rigid” in the building description refers to the structure’s ability to resist deformation and in no way reflects the building’s ability to be customized or modified.

Modular Building Prices vs. Metal Building Prices

Benefits of Rigid Buildings

Whether used in low-rise commercial buildings or skyskrapers, rigid frame buildings offer clear span framing, which is perhaps its most valuable feature in addition to its design capabilities. Clear span framing uses no interior columns because the building load is transferred to the side of the building. That leaves hundreds of feet of open space, making rigid frame buildings ideal for agricultural buildings, recreational facilities, factories, storage buildings and warehouses.

Portable Buildings vs. Metal Buildings

Pros and Cons Recap: Rigid Frame Buildings

Clear span capabilites up to 300’Fabrication timelines can be 3-6 weeks
I-beam construction = stronger structureEasy to get tricked into buying an inferior building
Can be erected quickly and can use piersOn-site construction costs will add to the final project price
Rigid Framing is No Longer Just a Metal Box
Burj Al Arab Rigid Framing

Photo Credit: Jumeirah

The modern steel building, including rigid frame buildings, has outgrown its “metal box” reputation. No longer are these facilities limited to static designs and bland execution. Rigid frame buildings offer endless possibilities for attractive AND useful facilities. To get a sense of just how versatile these buildings have become, take a look at Dubai’s Burj Al Arab Jumeirah, the self-proclaimed “most luxurious hotel in the world”.

While this example represents an impractical extreme in building design, its structural foundation is the product of the same framing concepts that make pre-engineered metal buildings the most trusted construction method in the world. It’s also a prime example of how versatile the framing used in a General Steel building can be.

Versatility in Design

Over the past several decades General Steel has demonstrated just how versatile rigid frame construction can be. General Steel buildings are often the most economical and always the most durable solution whether you’re building a fitness center, metal home or a workshop.


Workshop Building Design

Metal Home

Metal Home

Fitness Center

Metal Building Fitness Center

Need Help? We’re Listening

Modular buildings and rigid frame buildings are both great choices depending on your steel building needs. Each construction method results in a finished and professional product that achieves efficiency, quality and safety. If you’d like to take a look at modular building prices versus rigid frame building prices, contact us at 1-800-745-2685, or price your building online in three easy steps.

Pricing Answer

Building A: Modular building found on eBay

Building B: Price range for a 24′ x 48′ General Steel building.

*Pricing for General Steel building is a base building package only, does not include any components or interior finish. Local codes and loads may also change the pricing.


Modular Buildings vs. Rigid Frame Buildings
Article Name
Modular Buildings vs. Rigid Frame Buildings
Choosing the right type of building is critical. Learn the difference between 2 common steel structures in today’s market: rigid frame & modular buildings.
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General Steel
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