What is snagging a beam end?
Snagging (or snaping) a beam end is the practice of cutting the tip of a timber beam, rafter or purlin at an angle, creating a chamfered (snagged) end. The point of the timber is removed on a slope rather than left square.
Why snag a beam end?
Snagging beam ends serves several purposes:
- Moisture protection — a snagged beam end built into a wall sheds water more effectively and prevents moisture build-up
- Fire safety — historically, beam ends were snagged so that a beam could fall freely in a fire without pulling the wall down
- Installation — a chamfered end fits more easily into a beam pocket or joist hanger
- Aesthetics — in exposed timber structures, snagged ends provide a neat, traditional finish
Applications
- Roof construction — rafter and purlin ends are often snagged where they project through or beyond the wall
- Timber frames — in historic timber-framed buildings, beam ends are almost always snagged
- Floor joists — joist ends built into masonry walls are snagged to allow free movement
- Eaves overhang — the ends of projecting rafters are snagged for a tidy appearance
Related terms
- Beam
- Rafter
- Purlin
- Eaves
- Timber frame
Want to learn more about construction terms? Visit our knowledge base at fredsdiyplans.com.