Imagine building a Lego structure; choosing a block, lifting it, and casually placing it in the perfect position for your masterpiece. Now, imagine a Lego building so big that, instead of your arm, the lifting is done by a crane.
In the simplest of terms, that is what happens in the installation phase of modular construction. Pre-constructed modules of varying dimensions are hoisted by crane onto a temporary or permanent foundation in a process we affectionately describe as “Lego for Adults.”
Prior to installation, each individual module is manufactured off-site in a temperature-controlled facility, avoiding exposure to the elements and ensuring a strong final product. When manufacturing is complete, the modules are transported by truck to their site, where a building foundation has already been laid while the modules were being constructed.
Modular buildings can typically be placed on the same types of foundation as conventional builds. The design of the modules is simply tailored to the required foundation – grade-beam, slab on grade, steel and concrete piles, raft, parkade, or other types. The below image shows a crawl space foundation, which leaves open space underneath the ground floor modules to complete any final hook-ups of electricity, water or other utilities.
With a foundation in place, the cranes take over. The lift process can take 30 to 60 minutes per module, allowing 8 to 12 modules of a typical size to be placed per day dependent on the conditions. Before units are hoisted, the installation team completes extensive safety checks. They plan routes for the lift, account for or move obstacles in the path of the crane, and test the straps that bear the weight of the module while it is lifted.
As it lowers the module into place, the crane can get the unit nearly perfectly aligned with its final location. Members of the installation team use crowbars to guide the unit the remaining slivers of an inch into place, ensuring a seamless transition between modules.
The on-site process in modular construction bears little resemblance to site-built construction. To visualize the difference, think about going on a weeklong vacation only to return to a three-storey hotel where there was nothing before. Because of this key difference and because it is just beginning to gain popularity in Canada, installations typically bring out curious community members, who often stop to peer over the fence as the crane does its work.
The Benefits of Modular Construction
With the ability for modules to be sized appropriately to a customer’s needs, modular construction lends itself to any number of uses, including hotels, senior and student living, affordable housing, and residential homes. Its significant improvements over site-built construction include:
- Superior quality – Modular projects are subject to stringent internal quality assurance and control processes, which are confirmed by on-site third-party inspectors.
- Cost certainty – Costs remain on track as time delays due to weather, minimal trade availability, accident damage or theft are virtually eliminated.
- Sustainability – The lean modular construction process cuts down significantly on waste and improves efficiencies.
- Timetable certainty – With manufacturing occurring in a controlled environment at the same time as foundational work on the eventual site, the overall project time can be reduced by up to 50 per cent.