We talk a lot about modular construction (of course we do – it’s how we build!) but did you know that modular is just one of several methods of offsite construction?
Offsite construction refers to building techniques that see anything from individual components to an entire building constructed in a different location than the final site. Typically, the construction occurs in a manufacturing facility and the finished product is transported to its final location to be integrated into the final structure.
Let’s look at some of the different methods of offsite construction and what makes them each different, starting with a longer look at modular construction, which Horizon North and Karoleena use to create projects that matter for our customers across western and northern Canada.
In modular construction, sections of a building (modules) are manufactured offsite in a temperature-controlled facility. Those modules are then transported to their final site, set on the foundation footprint by crane, and joined together to make one integrated building. Once the modules are assembled onsite and the integration is complete, the structure is virtually indistinguishable from those built by traditional construction methods.
Two of the most significant benefits that modular construction provides over conventional methods are timetable reduction and scheduling certainty. Manufacturing occurs in a controlled indoor environment at the same time as foundational work occurs on the eventual site, which means timelines to completion are greatly reduced. Those timelines remain on schedule because delays due to weather, labour shortages and damage are minimized.
Among the other benefits that modular construction offers over site-built are:
- Superior quality – Modular projects are subject to stringent internal quality assurance / quality control processes, which are then confirmed by on-site third-party inspectors.
- Cost certainty – Cost overruns are minimized as 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. On the final site, the construction footprint is greatly reduced as well, with less noise, dust and vehicle traffic occurring over a shorter period of time.
Where modular construction builds components of a structure offsite, prefabricated (prefab) construction often sees an entire structure, with the exception of any foundations, constructed offsite and delivered to its final location. Prefab is most often used for structures like mobile homes that are easily relocated from site to site.
Precast construction uses concrete which is cast in a reusable mold and cured in a controlled environment to build components like frames, walls and doors. Once complete, the concrete formations are transported to the final site and installed.
Panelized construction brings conventional construction framing and wall assembly into an indoor, controlled manufacturing environment by using sophisticated computer software to guide construction. As with other forms of offsite construction, when the panels are complete, they are transported to site and installed as part of a final, integrated structure.
Componential or ‘Pod’ Construction
In ‘pod’ construction, certain pieces of a build are constructed offsite and then integrated into a more traditional overall build. Examples of the components that could be built and integrated using this method include modular concreate foundations or bathroom pods, where complex mechanical work can be done offsite and then installed as part of framing.
Pre-Assembled Steel Frame
In this form of offsite construction, steel frame components are pre-fabricated in a controlled manufacturing environment, and delivered and assembled as part of a final structure on-site. The installation process is a larger version of the toy erector sets many of us would have played with as children.
Another use for steel frames is smaller arch systems which are constructed indoors and then installed on a site. The appearance is that of a quonset, with an arched roof that provides extra capacity for snow and reduced maintenance.
Cross-laminated timber (CLT) is created by gluing and pressing perpendicular layers of lumber together into a single, rigid wood panel product. The panels are manufactured offsite and can be used to assemble exterior walls, floor, partition walls or roofs. Cross-laminated timber replaces concrete components of a building, reducing the carbon footprint while exceeding the fire suppression capabilities of a typical wood structure as a result of the additional thickness and rigidity.
Karoleena and Horizon North – Your Partners in Modular Construction
Karoleena’s parent company, Horizon North, is excited to be exhibiting at the 2018 Offsite Construction Expo on June 21 in Vancouver. Stop by our booth to learn more about our residential and commercial modular construction solutions.
Joe Kiss, our Senior Vice President, Modular Solutions, will be speaking alongside Luke Harrison of the Vancouver Affordable Housing Agency about the success of Horizon North modular buildings in addressing homelessness in Vancouver.