What size trusses do I need for a 24x24 garage in Miramichi NB snow country?

For a 24x24 garage in Miramichi, you need engineered roof trusses designed for a 24-foot clear span with a ground snow load of approximately 3.0 to 3.5 kPa, which is the design value for the Miramichi area under the National Building Code of Canada. Truss sizing is not something you can determine from a generic chart — every truss for an NB garage must be engineered by a truss manufacturer for your specific span, spacing, roof pitch, and local snow load.

A typical truss configuration for a 24x24 garage in Miramichi would be a common Fink or Howe pattern truss with a clear span of 24 feet, a roof pitch of 4/12 to 6/12 (steeper pitches shed snow better and are recommended in Miramichi's heavy snowfall zone), and a spacing of 24 inches on centre. The truss members themselves are typically made from 2x4 SPF lumber for lighter residential loads, though the engineer may specify 2x6 top chords depending on the snow load, pitch, and spacing combination. Steel connector plates join the members at each joint, and the entire truss is stamped with its design load rating.

Why Engineered Trusses Matter in Miramichi

Miramichi sits in one of NB's heavier snow load zones. The ground snow load of 3.0-3.5 kPa translates to roughly 60-70 pounds per square foot of accumulated snow on the ground, and the roof snow load (which accounts for factors like wind exposure, roof slope, and accumulation patterns) can be substantial. Add the possibility of rain-on-snow events — common in NB's Maritime climate where mid-winter thaws are followed by refreezing — and the loads on your garage roof can exceed what generic or undersized trusses can handle. A roof collapse under snow load is catastrophic and entirely preventable with properly engineered trusses.

When you order trusses from an NB truss manufacturer (such as companies in the Moncton or Fredericton area that serve Miramichi), you provide the building dimensions (24x24), roof pitch, overhang dimensions, truss spacing, and your exact location. The manufacturer's engineer designs the trusses for your site-specific snow load and wind load, produces sealed engineering drawings, and stamps each truss. This engineered drawing is a required document for your building permit application in Miramichi.

For a 24x24 garage, you will typically need 13 common trusses at 24-inch spacing (12 bays plus one), plus any specialty trusses for gable ends. If you want a steeper pitch — say 6/12 or 8/12 — to create storage space in the attic or to shed snow more aggressively, the trusses will be taller but can use the same lumber dimensions because the steeper angle distributes the load more efficiently. A 6/12 pitch is an excellent choice for Miramichi — it sheds snow well, provides some attic storage space, and is a good balance between material cost and performance.

Practical tips for truss ordering in Miramichi: Order your trusses 4-6 weeks before your build date — manufacturing lead times in NB can be 3-5 weeks during the busy spring and summer season. Budget approximately $3,000-$5,000 for the truss package for a 24x24 garage, depending on pitch and complexity. Ensure your foundation walls and top plates are level and square before truss delivery — trusses are precision-engineered and do not accommodate out-of-square structures well. Truss installation requires a crane or boom truck and a crew of at least 3-4 workers — this is not a two-person job.

Never attempt to build your own trusses or substitute site-built rafters for engineered trusses on a 24-foot span in NB snow country. The loads involved are serious and the consequences of failure are dangerous. Hire a professional garage builder who will coordinate the truss engineering, delivery, and installation as part of your complete garage project. Find local garage construction contractors through the New Brunswick Construction Network directory at newbrunswickconstructionnetwork.com.