Roofing Glossary

Collar Tie

Collar ties are horizontal boards that connect pairs of opposing rafters, typically in the upper third of the attic near the ridge. Their job is to resist the rafters spreading apart under roof loads — keeping the triangle rigid.

Collar ties work in tension: when snow or wind loads push the roof down and outward, the ties hold the rafter pairs together. Building codes specify their size, spacing, and placement — usually every other rafter pair, in the upper third of the span.

Homeowners encounter collar ties when finishing attics: they run right through the space you want to stand in. They can sometimes be relocated higher by an engineer, but they cannot simply be removed — doing so invites the rafters to spread and the ridge to sag.

Why It Matters

That board blocking your attic renovation is structural. Any plan to remove or relocate collar ties needs engineering approval first.

Questions about your own roof? Request a free estimate or call Nucci Brothers Roofing at (301) 458-1003.