By Ted McIntyre
Factory construction can offer a way past some of builders’ biggest impediments
If you like surprises, this probably isn’t for you. Consistency, after all, is a hallmark of modular construction, whereby a building is constructed off-site, under controlled factory conditions, using the same materials and designing at least to the same codes and standards as conventionally built facilities.
It’s topical at the moment, but hardly a novel concept. Online publishing platform Medium.com notes that the first documented prefabricated home was created in the 1830s “by London carpenter John Manning for his son, who was moving from England to Australia. Manning built a prefabricated house in pieces, then shipped it to the Land Down Under for easy assembly.”
An ad in the May 1, 1922 edition of MacLean’s magazine, meanwhile, promotes a ready-built summer cottage from Brantford’s Schultz Brothers measuring 16’ x 32’, with five rooms and a verandah—all for $699.95, including hardware, windows and doors.
A century later, the merits of manufacturing in a controlled, efficient, predictable and virtually error-free environment has been the theme of Working with Modular, an ongoing six-part webinar series hosted by the Canadian Home Builders’ Association over the past year. The content is designed to inform builders and developers, code officials, government departments, lenders, warranty providers, municipal planners and housing specialists, as well as other stakeholders engaged in the residential construction industry.
As of 2019, the modular sector included 216 factories certified to Canadian standards, 181 of which were located in Canada. They serve the range of residential occupancy from garden suites and single-family homes to multi-storey projects, employing 30,000 full-time workers, with $6 billion in economic activity.
“Factory-built construction is catching on as builders look for solutions to address the skilled labour shortage, improve productivity and to maximize much-needed housing supply to provide more homes to people at a price they can afford,” says webinar series co-host Frank Lohmann, CHBA’s Director of Building Science and a 23-year veteran of the National Building Council before joining CHBA in 2020. “CHBA is seeing a growing interest in the high level of environmental performance and full range of single- and multi-family design options achieved with modular construction. That’s most recently evidenced by the very high participation in our webinar series.”
That included more than 300 registrants from throughout the industry for the December webinar alone, which addressed the factory-built process. Those tuning in identified an even distribution of interests, ranging from sustainable construction to cost savings and scheduling.
Alberta’s Triple M Housing was front and centre in the December webinar. Its sprawling Lethbridge site spans 31 acres, the main factory of which measures 192,1000 square feet, along with a separate 12,000 sq. ft. saw shop and a welding facility. The company employs more than 400, including staff for customer support and warrantees, with both day and night shifts.
Inside the factory are 21 workstations and 12 drywall stations, churning out floor sizes up to 30’ x 76’, with each home requiring 10-21 days to complete.
Triple M’s step-by-step factory tour and assembly line-like automation served as a reminder of the amount of work that can be done before the finished product is shipped to site, including mechanical installations, such as prewiring and electrical panels, plumbing lines and vents, and even appliances, cabinetry and surfaces. And it all comes in a nicely sealed package.
“One of the tremendous advantages of factory-built construction is that it lends itself to creating an airtight building,” notes Triple M’s V.P. of Manufacturing and CHBA Modular Construction Council committee member Simarjit Bains. “Each wall, each floor, each storey is built from the inside out, which provides for easy and effective installation of insulation. There are no gaps in corners, behind electrical outlets or other hard-to-reach areas.
“Once the wall and floor panels have been put together to create volumetric models, they get finished really much the same way as on-site construction, except that this happens in a dry, warm environment with the help of cranes, and in some cases utilizing much larger material sizes for higher efficiency and fewer cut-offs,” Bains adds. “The safety railing system above and the flat firm factory working surface makes scaffolds easy to use and safe, leading to fewer accidents. And waste removal and recycling are simple and quick.”
Finished modules and sections can travel on the road or rail, as well as by air and water (Canadian provinces also export modules overseas), before being assembled on site.
The ability to work on the site foundation and the construction of the superstructure simultaneously accounts for most of the time savings, which are significant, as evidenced in the North Ridge CO2 Analysis Report, prepared by Dr. Mohamed Al-Hussein, PhD and Associate Professor of Construction Engineering and Management at the University of Alberta. The report, which analyzed the 42-suite, four-storey North Ridge residential building in St. Albert, Alberta, concluded that modular construction resulted in a 43% reduction in CO2 emissions and a 55% scheduling savings, with an overall construction time of 6.3 months compared to the 14.25 months of traditional on-site construction.
Alberta’s Landmark Homes, which used conventional stick-built construction from 1977-2005, before moving to automated panelized construction in 2005, provides Dr. Al-Hussein with another illuminating case study. “First off, the cycle time of panelize production rate,” Al-Hussein says.
Factors contributing to the reduction included fewer uncertainties related to handing off to different trades, a smoother turnover from house to house and higher predictability.
The number of superintendents required to inspect those finished products was reduced from 46 to 27, resulting in a 41% decrease in superintendent salary payment. It also led to a roughly 40% reduction of pickup truck use, which correspondingly reduced fuel consumption by 22,682 litres/year, leading to 52.46 fewer tons of annual CO2 emissions.
Then there’s the huge reduction of permits and inspection costs for things like HVAC, plumbing and gas, electrical and building codes, Dr. Al-Hussein indicated. “With stick-build construction, there’s an average of two additional inspections for each area, or eight total, for an additional cost of $2,160. With panelized construction, no additional inspections are required.”
The savings extend right down to the number of invoices and the time to process each. Another dramatic cost savings was associated with the shrinking of required office space, which dropped by 76%—from to 33,798 sq. ft. in 2005 to 7,956 sq. ft. in 2020.
Quality Assurance
Bains highlights the heightened degree of quality control that factory production provides, from every cut and measurement to the stability of materials in a climate-controlled environment—a far cry from traditional sites exposed to the whims of Mother Nature. Each component is checked and documented at every stage, Bains notes, with a travel log accompanying the factory checklist for all homes/modules, with each unit having a unique serial number.
All new buildings, whether site- or factory-built, must comply with the local building codes and regulations. However, for compliance of the work completed away from the building site, the administrative provisions of Division C of the National Building Code permit an off-site review to determine compliance with this code. Off-site review is done through certifying the entire factory construction process to the CSA A277 standard, which covers the factory’s quality program, auditing and in-plant inspections. So if a factory-constructed building in Canada bears the label of an accredited certification body (CSA, Intertek, Quality Assurance International, etc.), that body guarantees that the work completed in a factory meets the requirements of the local codes and regulations in effect at the installation site. That then provides local inspectors with assurance that concealed components that they cannot inspect, as well as other factory-built parts of the home, do not require re-inspection on this site. Further, the CSA A277 standard also sets requirements for personnel, their qualifications, schedules for inspection, labelling requirements and compliance procedures.
An added bonus is that modules also tend to exceed the wind resistance requirements of conventionally built homes, since they must be code-compliant to handle the potential stresses and high winds associated with road travel to the home site.
As local codes go, though, “municipal bylaws still need to be reviewed, as they set restrictions for factory-built housing in the context of architectural styles,” Lohmann says. “In addition to code compliance, we also often stress to municipalities that factory-built housing can easily meet the same architectural design guidelines as site-built. And some municipalities may also not realize that factory-constructed housing solutions can also help them meet many of their policies, such as affordable housing, age-friendly housing, secondary suites and garden units or, in general, sustainable design.”
Modular in Ontario
Arguably the most high-profile modular construction project in the province of Ontario is currently EVE Park in London, Ontario’s Riverbend community. Ellis-Don is constructing four buildings in two phases, using modular components produced by TRS Components Ltd. from the nearby town of Thornbury. “Each panel is manufactured off-site to fit precisely where it needs to go before being officially assembled. Faster, cleaner, stronger and with generally better quality,” the project’s website explains. A total of 84 units will be divided equally across the four buildings, with August occupancy planned for Building A, and October for Building B. Occupancy dates for Phase 2 (Buildings C and D) have not been released.
“This is our first modular project in Canada,” says project lead Ashley Hammerbacher from the San Francisco office of St. Jacob’s, Ontario-based s2e Technologies. “We chose panelized modular construction because we believed that it would save time, reduce in-field mistakes, reduce material waste and improve quality.”
Royal Homes is well aware of the advantages, even touting that it “revolutionized the local building industry by blending traditional craftsmanship with modern technology to produce high quality custom homes that are built better and faster than outdoor-built homes.” Founded in 1971, Royal’s headquarters and 110,000 sq. ft. factory are located in the North Huron community of Wingham. The company is seeing increased traffic through its doors, with recent projects varying from handsome 1,155 sq. ft. bungalows to sprawling luxury lakeside cottage country residences.
“On average, our homes are completed turnkey in as little as six to nine months after signing,” says Royal’s Matt Steffler, whose company is noted for its design centres and wealth of options for prospective homebuyers. Its 250-point inspection is similarly as detailed. Further, Royal extends the seven-year Tarion-backed structural warranty three additional years, including a five-year no-leak foundation warranty.
On the renovation side, Toronto-based Modular Homes Additions has completed over 1,000 construction projects since its founding in 2000 and is taking advantage of its ability to do big things in restricted areas. “In the city, the best way to put an addition is to go up, since the lots are usually quite narrow and do not allow for ground additions. The modular addition system was developed so that bungalows can be topped up within three to five days,” says Bole Cirovic, director of sales and marketing at Modular, which has its own factory in East York. Although its construction process is not automated, “it is done in modules off-site in our climate-controlled facility,” Cirovic notes. “Another key advantage is convenience. Our clients can stay in the house during the construction, and installation of the shell is done quickly and without much mess on the site, meaning less hassle for both owners and neighbours.”
Through CreateTO, the City of Toronto has also been capitalizing on modular construction for supportive housing projects such as 11 Macey Avenue, a 56-unit, three-storey apartment building with a dining room and common rooms that opened in December 2020—just eight months after being approved by City Council, and 321 Dovercourt Rd. (three storeys with 44 units and similar added facilities), which opened nine months after approval.
Another plus is occurring on the job front, Lohmann explains. “While factory construction provides reliable access to skilled labour, it also broadens the labour pool in two ways. Number one, it can require other types of skilled workers, like machine operators or robotics specialists. And some modular construction workers may work at single stations and may be able to work on a narrower scope of their work, and therefore may not need the same breadth of skills that tradesmen on the traditional site would require. These two features reduce the dependency on the same labour and skills as on-site construction.
“To be clear though, it’s not necessarily less labour to build modular houses,” Lohmann says. “But where a shortage of labour exists, panelized modular construction may add capacity to supplement on-site builders.
“I think there needs to be more information about these kinds of benefits, and the webinar series is the first step,” Lohmann adds. “Hopefully each of the participants have conversations in their area of practice to incorporate some of these ideas. That’s how we can scale this faster.
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