Can I cut a web if I need to move a duct?

No, trusses are engineered systems; cutting or moving any member results in immediate structural failure risk and requires an engineer's repair seal.

What is the standard lead time for ordering?

Typical production lead time is 4 to 8 weeks, depending on order volume and material availability.

Do I need a permit for trusses?

Yes, truss layout and engineering stamps are required by most local building departments as part of the residential building permit application.

What is a 'heel' height?

The heel is the vertical depth of the truss at the exterior wall, which determines the amount of insulation that can be placed at the eaves.

Trusses

Roof

$6 to $14 per square foot of roof footprint, depending on complexity, span, and regional lumber indices.

Roof Trusses: Technical Specifications and Engineering Requirements (2026)

Prepared by Lumberama's Building Materials Team

|Last updated September 3, 2026|Sources & methodology

Roof trusses are structural frameworks composed of chords and webs arranged in triangular patterns to support roof loads over varying spans. Engineered to redistribute loads to exterior bearing walls, trusses are typically fabricated from kiln-dried SPF or SYP lumber joined by galvanized steel connector plates.

Key Features

Custom-engineered to specific job site load requirements. - Standardized manufacturing ensures consistency across rafters. - Web configurations allow for open floor plans without interior load-bearing walls. - Reduced material waste compared to stick-framed roofing. - Factory-controlled quality under strict QC standards.

Specifications

Chord Thickness: Typically 2x4 or 2x6 framing lumber. - Plate Connectors: 20-gauge to 18-gauge galvanized steel plates with integral teeth. - Spans: Standard clear spans up to 60 feet common; larger spans require specialized design. - Spacing: Usually 16

19.2

or 24 inches on center. - Pitch: Available in any slope from flat to 12/12 and higher.

Applications

Residential single-family homes. - Multi-family residential complexes. - Light commercial structures. - Agricultural outbuildings and barns. - Attic storage configurations (Room-in-attic trusses).

Installation Overview

- Trusses must be set on load-bearing walls with proper anchor straps. - Bracing is mandatory during installation to prevent lateral buckling. - Permanent bracing must be installed according to the truss design engineer's drawings. - Crane or boom truck lift is standard for safety. - Ensure all connections meet uplift requirements for local wind zone ratings.

Pros & Cons

Pros

✓ Rapid on-site assembly. - High strength-to-weight ratio. - Precision engineered for specific structural loads. - Less field cutting required compared to stick framing.

Cons

✗ Limited attic accessibility in standard designs. - Cannot be modified or cut in the field without engineering approval. - Requires heavy machinery for installation. - Long lead times for custom fabrication.

Code Requirements

- Must be designed by a licensed professional engineer (PE). - Subject to IRC (International Residential Code) structural load standards. - Requires engineered seal and sign-off for local building permit approval. - Must adhere to local snow load and wind uplift requirements.

Buying Tips

- Provide accurate exterior dimensions and interior bearing wall locations. - Specify the desired roof pitch and heel height. - Request shop drawings for review prior to final production. - Account for 4-to-8 week lead times during peak building seasons.