Should I use engineered floor trusses for a second-storey garage loft in Riverview NB?

Engineered floor trusses are an excellent choice for a garage loft in Riverview, and in most cases they outperform traditional dimensional lumber joists for this application. The decision comes down to your span, your intended use of the loft space, and how the floor system integrates with your garage's overall structure.

Why Engineered Trusses Make Sense for NB Garage Lofts

The core advantage of open-web floor trusses over solid lumber joists is the combination of longer clear spans, consistent dimensional stability, and the open web cavities that let your trades run mechanical, electrical, and HVAC through the floor system without drilling through joists. For a typical Riverview garage loft — say a 24x24 or 24x30 footprint — dimensional lumber joists in the 2x10 or 2x12 range start to struggle at spans beyond 14-16 feet without a centre beam breaking up the span. Engineered floor trusses can routinely handle 20-28 foot clear spans with no intermediate support, which means the garage below stays open and column-free. That matters enormously if you want to park two vehicles side by side without a post in the middle of the bay.

The other critical factor in Riverview specifically is live load design. A loft used purely for storage is typically designed for 40 pounds per square foot (roughly 2.0 kPa) live load. But if you're planning a finished bonus room, home office, or any occupied space, the design load jumps to the same standard as a residential floor — and the floor system must be engineered accordingly. Riverview sits in a Moncton-area market where building inspectors are active and thorough, so your floor system will be reviewed against the NB Building Code. Engineered trusses come with stamped engineering documentation that satisfies this requirement cleanly, whereas a contractor specifying dimensional lumber for a long-span loft floor needs to demonstrate code compliance through span tables, which gets complicated quickly.

Deflection and Bounce — A Practical Reality

One thing homeowners don't always anticipate is floor deflection, the slight springiness or bounce underfoot. Dimensional lumber floors over long spans can feel noticeably springy, which is uncomfortable in a living or office space and can cause drywall cracks in a finished ceiling below. Engineered floor trusses are designed to a tighter deflection limit (typically L/480 for finished applications versus L/360 for basic structural compliance), which produces a stiffer, more solid-feeling floor. If you're finishing the loft as a bonus room — a popular choice in Riverview where lot sizes support larger garage footprints — this stiffness difference is something you'll notice every day.

NB-Specific Considerations

Riverview's climate means your garage loft floor system sits in a zone that experiences significant temperature and humidity swings. Dimensional lumber is more susceptible to seasonal movement, cupping, and shrinkage than engineered products, which are manufactured to stable moisture content and don't behave the same way when the garage goes from -20°C in January to humid Maritime summer conditions. This seasonal movement in solid lumber can cause squeaky floors, nail pops in drywall, and gaps at trim over time. Engineered trusses and I-joists are far more dimensionally stable through NB's seasonal extremes.

Also worth noting: if you're adding in-floor radiant heating to the loft (a luxurious but practical choice for a finished bonus room in NB), the open web cavities in floor trusses make routing the hydronic tubing or electric heating elements significantly easier than drilling through solid joists.

Practical Tips

The floor truss package for a 24x24 garage loft typically runs $3,500-$6,500 for materials, depending on span, spacing, and load requirements — more than a dimensional lumber alternative, but the labour savings from faster installation and easier mechanical rough-in often offset a significant portion of that premium. Your truss manufacturer (Trus Joist, MiTek, and similar suppliers serve the Moncton-Riverview market) will require a floor plan and loading information to produce shop drawings, which your contractor coordinates.

This is firmly in professional territory — floor truss layout, bearing point design, and connection to the garage wall framing all require a contractor experienced with engineered lumber systems. The truss manufacturer provides the engineering, but proper installation, blocking, rim board details, and connection to the wall top plate must be executed correctly to perform as designed.

If you're planning a garage loft in Riverview and want to get matched with a contractor experienced in this type of build, New Brunswick Garages can connect you with local professionals through the New Brunswick Construction Network — find garage builders in your area at newbrunswickconstructionnetwork.com/directory?category=general-contracting.