The Last Word on Multi-Family

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The Last Word
Issue #14274 - May 2022 | Page #126
By Joe Kannapell

Has COVID-19, its aftermath, and raging inflation brought the multi-family truss business back to its roots? Bo Powers, co-owner of Panel Truss, sees fewer wraps and more garden style jobs further from cities. Kenny Shifflett, owner of Ace Carpentry, believes the plethora of these “cornfield” jobs may be a passing phase, as Gen Z (born 1996–2010) prefers inner city housing, or apartments near transit stations. How might this affect the truss business? [For all images, See PDF or View in Full Issue.]

Garden apartment truss jobs, especially in prosperous areas, provide steady, repetitive work, especially in floor trusses. Jobsites are larger and easier to access and trucks are offloaded quicker. Even as buildings have gotten taller and more expansive, they’ve retained some similarity to one another. However, keeping apace with construction can overtask a facility and risk crowding out single family work. And that risk becomes even greater with the wraps and podiums.

Large monolithic apartment buildings began springing up around the new Millennium as Millennials began moving into cities. To make their new abodes affordable, the old densities of 19–25 units per acre had to be doubled or even tripled, giving rise to the new typologies of wraps, donuts, and podiums. Parking areas have to be stacked, requiring concrete structures, that are concealed either behind or beneath the wood framed structure. Roof trusses often must be designed for the added loading resulting from rooftop recreational spaces or green areas that take the place of expensive ground level open spaces.

The Wraparound or Wrapped buildings position their living units along the streetscape, blocking from view most of their concrete garages. Typically, these buildings are located in less-densely populated city edges, are usually topped out at 4 stories, and must follow provisions of the International Building Code (IBC) for Type V structures.

The Texas Donut, a term coined by Trussway, is a special case of the Wrap in which the living units totally surround the unsightly garage and are ideally suited for infill locations. The perimeter outline of structure is generally rectangular, but the center may combine open spaces with the parking garage, as shown.

Podium apartment structures are framed on top of elevated concrete platforms and are designed under more stringent IBC Type III requirements. They may reach heights of 85 feet and contain up to 5 wood framed floors over two concrete stories, with very specific fire protection requirements. Exterior walls and adjacent structural elements must be two-hour fire rated, often requiring custom fire treatment of high grades of lumber. Their below-the-podium areas contain mostly well-ventilated parking areas, a significant plus in regions with inclement weather.

This type of building converts project management from a “by floor and by building” into a “by-zones” methodology and greatly complicates design. Because they contain a gargantuan number of framing elements, dividing these buildings into manageable zones without an “x-ref” software capability is an awesome challenge. This type of software enables a designer to setup and manipulate specific zones, ensuring that they fit properly into the rest of the structure. And this segmented project management must carry over into truss manufacturing and shipping, which both require incredible coordination in urban zones with negligible lay-down areas.

In summary, component manufacturers have developed increasingly sophisticated systems to successfully truss even the largest and most complex housing structures. Indeed, only because of CMs’ long history of successes are such complex buildings proliferating, providing the best values for residents in nearly every venue from inner cities to rural counties. While many garden apartment buildings can be trussed with ease, high density multi-family structures, built standalone, as wraps, or on a podium, require many times the expertise.

You're reading an article from the May 2022 issue.

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