diff --git a/M02_MasterTemplete/M02_MasterTemplete_UI_Page.ts b/M02_MasterTemplete/M02_MasterTemplete_UI_Page.ts
index cdb0e2d9..ec5f7c37 100644
--- a/M02_MasterTemplete/M02_MasterTemplete_UI_Page.ts
+++ b/M02_MasterTemplete/M02_MasterTemplete_UI_Page.ts
@@ -57,10 +57,18 @@ export async function renderM02MasterTemplate(root: HTMLElement): Promise<Mounte
     settle: () => main.settle(),
     onChanged: (colId) => main.openTable(layer, colId, true),
   });
+  // 일위대가 화면이 떠 있나 — 뿌리를 바꿔도(어느 뿌리 줄을 누르든) 일위대가로 다시 엶 ·
+  // 해시 `open` 도 맞춤(새로 고침 · 카드 진입과 같게) · 옵션 · 도면은 옛 규칙(구조물 조합으로)
+  let view: OpenTarget = entry.open;
+  const mark = (open: OpenTarget): void => {
+    view = open;
+    const query = new URLSearchParams(entryQuery({ ...entry, open }));
+    history.replaceState(history.state, "", `#/${ROUTES.M02_MASTER_TEMPLATE}?${query}`);
+  };
   const go = async (
     next: Root,
     nextOwner: string | null,
-    open: OpenTarget = "구조물조합",
+    open: OpenTarget = view === "일위대가" ? "일위대가" : "구조물조합",
   ): Promise<void> => {
     // 같은 주소 안 이동은 머리 가드가 안 물음 — 저장 안 한 고침은 여기서
     if (!(await main.confirmLeave())) return;
@@ -75,7 +83,7 @@ export async function renderM02MasterTemplate(root: HTMLElement): Promise<Mounte
       user,
       active: { root: entry.root, owner },
       panel,
-      go: (next, nextOwner) => void go(next, nextOwner, "일위대가"),
+      go: (next, nextOwner) => void go(next, nextOwner),
     });
   const roots = createLibraryRoots({
     user,
@@ -90,7 +98,11 @@ export async function renderM02MasterTemplate(root: HTMLElement): Promise<Mounte
   const main = createMain(
     isAdmin,
     () => void Promise.all([side.refresh(), tree.refresh()]),
-    () => side.paint(),
+    () => {
+      side.paint();
+      // 일위대가 화면에서 양식으로 옮김(일위대가 · 옵션 화면은 current 없음)
+      if (main.current() && view === "일위대가") mark("구조물조합");
+    },
     {
       top: readOnlyBar?.root,
       aside,
@@ -118,7 +130,10 @@ export async function renderM02MasterTemplate(root: HTMLElement): Promise<Mounte
       buildLaborSection({
         show: main.showView,
         confirmLeave: main.confirmLeave,
-        onOpen,
+        onOpen: () => {
+          onOpen();
+          mark("일위대가");
+        },
         make: () =>
           buildLaborLibrary({ scope: { layer, owner }, canEdit: isAdmin, roots: laborRoots }),
       }),
diff --git a/resources/tester/test_m02_labor_tree.py b/resources/tester/test_m02_labor_tree.py
index f766acf5..2b643578 100644
--- a/resources/tester/test_m02_labor_tree.py
+++ b/resources/tester/test_m02_labor_tree.py
@@ -74,3 +74,16 @@ def test_나무_고침_알림(got):
     assert rename_item["경로"] == ["석축", "나나"]
     assert "열" not in delete_item and delete_item["지운항목"] == ["UP1-000002"]
     assert "경로" not in delete_folder
+
+
+def test_뿌리를_바꿔도_일위대가_화면_유지_해시도_맞춤():
+    """브레인 검증 흠(27-2b) — 뿌리 줄은 두 벌(구조물 · 일위대가) · 어느 줄을 누르든 지금 화면 ·
+    좌측 「일위대가 라이브러리」를 열면 해시 `open=일위대가`(다시 그리지 않고 주소만)."""
+    page = (ROOT / "M02_MasterTemplete/M02_MasterTemplete_UI_Page.ts").read_text("utf-8")
+    assert 'open: OpenTarget = view === "일위대가" ? "일위대가" : "구조물조합"' in page
+    assert page.count("go: (next, nextOwner) => void go(next, nextOwner),") == 2  # 두 벌 같은 길
+    assert '"일위대가")' not in page.split("const laborRoots")[1].split("const roots")[0]
+    labor = page.split("buildLaborSection({")[1].split("make:")[0]
+    assert 'mark("일위대가")' in labor  # 여는 순간 해시 open
+    assert "history.replaceState" in page  # hashchange 없이(화면 다시 안 그림)
+    assert 'if (main.current() && view === "일위대가") mark("구조물조합")' in page
diff --git a/resources/tester/test_m02_structure_panel.py b/resources/tester/test_m02_structure_panel.py
index 1df1c34d..2a7c7d9b 100644
--- a/resources/tester/test_m02_structure_panel.py
+++ b/resources/tester/test_m02_structure_panel.py
@@ -188,7 +188,8 @@ def test_좌측_고름_표시는_열린_것_한_줄뿐():
     # 자재 조합 상세도 같은 한 곳 — 열면 양식 · 열 줄 고름 지움 · 양식을 열면 자재 조합 고름 지움
     assert re.search(r"sel = null;\s*onOpened\?\.\(\);", _text(MAIN))
     assert "if (opt.getOpen()) matset.clear();" in side.split("function paint(): void {")[1]
-    assert "() => side.paint()" in _text(M02 / "M02_MasterTemplete_UI_Page.ts")
+    # 편집 칸이 열 때마다 좌측 `paint`(27-2b 뒤 = 일위대가 화면 해시 맞춤도 같은 자리)
+    assert re.search(r"\(\) => \{\s*side\.paint\(\);", _text(M02 / "M02_MasterTemplete_UI_Page.ts"))
 
 
 def test_리본_접힘_모드에서_탭으로_편_것은_밖을_누르면_다시_접힘():