U-Pattern
Definition
A rounded variant of the V-pattern, associated with lower heat release rates and slower fire development; the broader base and higher apex reflect a less intense or longer-duration heat source than a sharp V.
- Relation to V-pattern
- Rounded variant with broader base
- Heat release rate
- Lower than a sharp V
- Development speed
- Slower fire development
- Apex shape
- Higher and less pointed than a V-pattern
Common questions
Why does a U-pattern suggest a different fire dynamic than a sharp V-pattern at the same location?+
A sharp V forms from a fast, intense heat source that scorches upward and outward quickly, while a broader, rounder U reflects a heat source that burned longer at lower intensity, so the pattern shape helps investigators infer fuel type and burn duration rather than only origin location.
Can a U-pattern alone establish where a fire started?+
It indicates the general area and suggests burn characteristics but must be considered alongside char depth, other burn patterns, and physical evidence, since ventilation and fuel load can alter pattern shape independent of the ignition source itself.
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