diff --git a/src/common/roofShapePattern.js b/src/common/roofShapePattern.js
index abba02a6..bf264c0f 100644
--- a/src/common/roofShapePattern.js
+++ b/src/common/roofShapePattern.js
@@ -126,3 +126,25 @@ export const matchRoofShapePattern = (descriptor) => {
 
   return candidate.shapeNum
 }
+
+// Gemini 자유 출력(raw) → 매처 strict 어휘로 정규화한 RoofShapeDescriptor | null.
+// 어휘 밖 type/ridge 는 ''(매처가 결측 관대), flows 는 ROOF_FLOW 어휘만 소문자화·중복제거.
+// type·ridge·flows 가 모두 비면 null. direction 은 산출하지 않는다(매처 미사용).
+export const normalizeRoofShape = (raw) => {
+  if (!raw || typeof raw !== 'object') return null
+
+  const norm = (value) => (typeof value === 'string' ? value.trim().toLowerCase() : '')
+  const TYPE_VALUES = Object.values(ROOF_SHAPE_TYPE)
+  const RIDGE_VALUES = Object.values(ROOF_RIDGE)
+  const FLOW_VALUES = Object.values(ROOF_FLOW)
+
+  const type = TYPE_VALUES.includes(norm(raw.type)) ? norm(raw.type) : ''
+  const ridge = RIDGE_VALUES.includes(norm(raw.ridge)) ? norm(raw.ridge) : ''
+  const flows = Array.isArray(raw.flows) ? [...new Set(raw.flows.map(norm).filter((flow) => FLOW_VALUES.includes(flow)))] : []
+
+  if (!type && !ridge && flows.length === 0) return null
+
+  const result = { type, ridge, flows }
+  if (typeof raw.confidence === 'number') result.confidence = raw.confidence
+  return result
+}