diff --git a/src/App.tsx b/src/App.tsx
index daa22cb..f4615c2 100644
--- a/src/App.tsx
+++ b/src/App.tsx
@@ -569,6 +569,11 @@ export default function App() {
   const setSelectedCeilingIds = useStore((s) => s.setSelectedCeilingIds);
   const selectedCeilingId =
     selectedCeilingIds.length === 1 ? selectedCeilingIds[0] : null;
+  // Dach-Auswahl (MENGE); Einzel-Element bei genau einem gewählten Dach.
+  const selectedRoofIds = useStore((s) => s.selectedRoofIds);
+  const setSelectedRoofIds = useStore((s) => s.setSelectedRoofIds);
+  const selectedRoofId = selectedRoofIds.length === 1 ? selectedRoofIds[0] : null;
+  const updateRoof = useStore((s) => s.updateRoof);
   const selectedOpeningIds = useStore((s) => s.selectedOpeningIds);
   const setSelectedOpeningIds = useStore((s) => s.setSelectedOpeningIds);
   const selectedOpeningId =
@@ -618,6 +623,7 @@ export default function App() {
     setSelectedRoomIds([]);
     setSelectedExtrudedSolidIds([]);
     setSelectedColumnIds([]);
+    setSelectedRoofIds([]);
     setMenu(null);
     setEditor(null);
   }, [activeLevelId]);
@@ -1844,7 +1850,8 @@ export default function App() {
         selectedStairIds.length ||
         selectedRoomIds.length ||
         selectedExtrudedSolidIds.length ||
-        selectedColumnIds.length
+        selectedColumnIds.length ||
+        selectedRoofIds.length
       ) {
         const dids = new Set(selectedDrawingIds);
         const wids = new Set(selectedWallIds);
@@ -1854,11 +1861,13 @@ export default function App() {
         const rmids = new Set(selectedRoomIds);
         const exids = new Set(selectedExtrudedSolidIds);
         const colids = new Set(selectedColumnIds);
+        const rfids = new Set(selectedRoofIds);
         setProject((p) => ({
           ...p,
           drawings2d: p.drawings2d.filter((d) => !dids.has(d.id)),
           walls: p.walls.filter((w) => !wids.has(w.id)),
           ceilings: (p.ceilings ?? []).filter((c) => !cids.has(c.id)),
+          roofs: (p.roofs ?? []).filter((r) => !rfids.has(r.id)),
           stairs: (p.stairs ?? []).filter((s) => !stids.has(s.id)),
           rooms: (p.rooms ?? []).filter((r) => !rmids.has(r.id)),
           extrudedSolids: (p.extrudedSolids ?? []).filter((s) => !exids.has(s.id)),
@@ -1877,6 +1886,7 @@ export default function App() {
         setSelectedRoomIds([]);
         setSelectedExtrudedSolidIds([]);
         setSelectedColumnIds([]);
+        setSelectedRoofIds([]);
         e.preventDefault();
       }
     };
@@ -1892,9 +1902,11 @@ export default function App() {
     selectedStairIds,
     selectedExtrudedSolidIds,
     selectedColumnIds,
+    selectedRoofIds,
     project.walls,
     project.drawings2d,
     project.ceilings,
+    project.roofs,
     project.stairs,
     project.extrudedSolids,
     project.columns,
@@ -2559,6 +2571,7 @@ export default function App() {
         selectedRoomId,
         selectedExtrudedSolidId,
         selectedColumnId,
+        selectedRoofId,
       ),
     [
       project,
@@ -2570,6 +2583,7 @@ export default function App() {
       selectedRoomId,
       selectedExtrudedSolidId,
       selectedColumnId,
+      selectedRoofId,
     ],
   );
 
@@ -3116,6 +3130,10 @@ export default function App() {
         setResourcesTab(kind === "door" ? "doorStyles" : "windowStyles");
         setResourcesOpen(true);
       },
+      // ── Dach-Attribute (nur bei selektiertem Dach) ─────────────────────────
+      onSetRoofPatch: (patch) => {
+        if (selection?.kind === "roof") updateRoof(selection.id, patch);
+      },
       // ── Treppen-Attribute (nur bei selektierter Treppe) ────────────────────
       onSetStairShape: (shape) => {
         if (selection?.kind === "stair") updateStair(selection.id, { shape });
@@ -4220,93 +4238,61 @@ export default function App() {
             ? selectedColumnIds.filter((x) => x !== id)
             : [...selectedColumnIds, id],
         );
+      } else if (sel.roofId) {
+        const id = sel.roofId;
+        setSelectedRoofIds(
+          selectedRoofIds.includes(id)
+            ? selectedRoofIds.filter((x) => x !== id)
+            : [...selectedRoofIds, id],
+        );
       }
       return;
     }
     // Ohne Shift: ersetzen. Öffnung hat Vorrang (ihr Symbol liegt in der Lücke),
     // dann Wand, dann 2D-Element, dann Decke; sonst leeren. Die Kanäle schließen
     // sich gegenseitig aus.
+    // Alle Kanäle ausser dem gewählten leeren — als Helfer, damit jeder Zweig
+    // (inkl. des neuen Dach-Kanals) konsistent bleibt.
+    const clearOthers = (keep: string) => {
+      if (keep !== "wall") setSelectedWallIds([]);
+      if (keep !== "drawing") setSelectedDrawingId(null);
+      if (keep !== "ceiling") setSelectedCeilingIds([]);
+      if (keep !== "opening") setSelectedOpeningIds([]);
+      if (keep !== "stair") setSelectedStairIds([]);
+      if (keep !== "room") setSelectedRoomIds([]);
+      if (keep !== "extrudedSolid") setSelectedExtrudedSolidIds([]);
+      if (keep !== "column") setSelectedColumnIds([]);
+      if (keep !== "roof") setSelectedRoofIds([]);
+    };
     if (sel.openingId) {
       setSelectedOpeningIds([sel.openingId]);
-      setSelectedWallIds([]);
-      setSelectedDrawingId(null);
-      setSelectedCeilingIds([]);
-      setSelectedStairIds([]);
-      setSelectedRoomIds([]);
-      setSelectedExtrudedSolidIds([]);
-      setSelectedColumnIds([]);
+      clearOthers("opening");
     } else if (sel.wallId) {
       setSelectedWallIds([sel.wallId]);
-      setSelectedDrawingId(null);
-      setSelectedCeilingIds([]);
-      setSelectedOpeningIds([]);
-      setSelectedStairIds([]);
-      setSelectedRoomIds([]);
-      setSelectedExtrudedSolidIds([]);
-      setSelectedColumnIds([]);
+      clearOthers("wall");
     } else if (sel.columnId) {
       setSelectedColumnIds([sel.columnId]);
-      setSelectedWallIds([]);
-      setSelectedDrawingId(null);
-      setSelectedCeilingIds([]);
-      setSelectedOpeningIds([]);
-      setSelectedStairIds([]);
-      setSelectedRoomIds([]);
-      setSelectedExtrudedSolidIds([]);
+      clearOthers("column");
     } else if (sel.drawingId) {
       setSelectedDrawingId(sel.drawingId);
-      setSelectedWallIds([]);
-      setSelectedCeilingIds([]);
-      setSelectedOpeningIds([]);
-      setSelectedStairIds([]);
-      setSelectedRoomIds([]);
-      setSelectedExtrudedSolidIds([]);
-      setSelectedColumnIds([]);
+      clearOthers("drawing");
     } else if (sel.extrudedSolidId) {
       setSelectedExtrudedSolidIds([sel.extrudedSolidId]);
-      setSelectedWallIds([]);
-      setSelectedDrawingId(null);
-      setSelectedCeilingIds([]);
-      setSelectedOpeningIds([]);
-      setSelectedStairIds([]);
-      setSelectedRoomIds([]);
-      setSelectedColumnIds([]);
+      clearOthers("extrudedSolid");
     } else if (sel.ceilingId) {
       setSelectedCeilingIds([sel.ceilingId]);
-      setSelectedWallIds([]);
-      setSelectedDrawingId(null);
-      setSelectedOpeningIds([]);
-      setSelectedStairIds([]);
-      setSelectedRoomIds([]);
-      setSelectedExtrudedSolidIds([]);
-      setSelectedColumnIds([]);
+      clearOthers("ceiling");
     } else if (sel.stairId) {
       setSelectedStairIds([sel.stairId]);
-      setSelectedWallIds([]);
-      setSelectedDrawingId(null);
-      setSelectedCeilingIds([]);
-      setSelectedOpeningIds([]);
-      setSelectedRoomIds([]);
-      setSelectedExtrudedSolidIds([]);
-      setSelectedColumnIds([]);
+      clearOthers("stair");
     } else if (sel.roomId) {
       setSelectedRoomIds([sel.roomId]);
-      setSelectedWallIds([]);
-      setSelectedDrawingId(null);
-      setSelectedCeilingIds([]);
-      setSelectedOpeningIds([]);
-      setSelectedStairIds([]);
-      setSelectedExtrudedSolidIds([]);
-      setSelectedColumnIds([]);
+      clearOthers("room");
+    } else if (sel.roofId) {
+      setSelectedRoofIds([sel.roofId]);
+      clearOthers("roof");
     } else {
-      setSelectedWallIds([]);
-      setSelectedDrawingId(null);
-      setSelectedCeilingIds([]);
-      setSelectedOpeningIds([]);
-      setSelectedStairIds([]);
-      setSelectedRoomIds([]);
-      setSelectedExtrudedSolidIds([]);
-      setSelectedColumnIds([]);
+      clearOthers("");
     }
   };
   // Links-Drag (Marquee) im Grundriss: die getroffene Wand-MENGE übernehmen
@@ -4314,14 +4300,15 @@ export default function App() {
   const onPlanMarquee = (sel: MarqueeSelection) => {
     setSelectedWallIds(sel.wallIds);
     setSelectedDrawingIds(sel.drawingIds ?? []);
-    // Decken/Öffnungen/Treppen/Räume/Extrusionen sind (noch) nicht Teil des
-    // Marquee → beim Aufziehen abwählen.
+    // Decken/Öffnungen/Treppen/Räume/Extrusionen/Dächer sind (noch) nicht Teil
+    // des Marquee → beim Aufziehen abwählen.
     setSelectedCeilingIds([]);
     setSelectedOpeningIds([]);
     setSelectedStairIds([]);
     setSelectedRoomIds([]);
     setSelectedExtrudedSolidIds([]);
     setSelectedColumnIds([]);
+    setSelectedRoofIds([]);
   };
   // Rechts-Klick im Grundriss: Wand-Kontextmenü. Trifft der Klick eine Wand, die
   // NICHT bereits in der Auswahl ist, wird die Auswahl auf sie gesetzt (damit die
diff --git a/src/i18n/de.ts b/src/i18n/de.ts
index 7a0a92e..4ff6864 100644
--- a/src/i18n/de.ts
+++ b/src/i18n/de.ts
@@ -285,6 +285,25 @@ export const de = {
   "objinfo.kind.room": "Raum",
   "objinfo.kind.extrudedSolid": "Extrusion",
   "objinfo.kind.column": "Stütze",
+  "objinfo.kind.roof": "Dach",
+  // ── Dach-Attribute (Object-Info-Panel) ──────────────────────────────────
+  "objinfo.roof.section": "Dach",
+  "objinfo.roof.shape": "Dachform",
+  "objinfo.roof.shape.flach": "Flachdach",
+  "objinfo.roof.shape.pult": "Pultdach",
+  "objinfo.roof.shape.sattel": "Satteldach",
+  "objinfo.roof.shape.walm": "Walmdach",
+  "objinfo.roof.shape.mansarde": "Mansarddach",
+  "objinfo.roof.shape.zelt": "Zeltdach",
+  "objinfo.roof.ridgeAxis": "Firstrichtung",
+  "objinfo.roof.ridgeAxis.x": "entlang X",
+  "objinfo.roof.ridgeAxis.y": "entlang Y",
+  "objinfo.roof.pitch": "Neigung (°)",
+  "objinfo.roof.pitchUpper": "Obere Neigung (°)",
+  "objinfo.roof.overhang": "Überstand (m)",
+  "objinfo.roof.thickness": "Dachdicke (m)",
+  "objinfo.roof.ridgeHeight": "Firsthöhe",
+  "objinfo.roof.area": "Grundfläche",
   // ── Stützen-Attribute (Object-Info-Panel) ───────────────────────────────
   "objinfo.column.section": "Stütze",
   "objinfo.column.profile": "Profil",
diff --git a/src/i18n/en.ts b/src/i18n/en.ts
index 64be6bc..8f5005e 100644
--- a/src/i18n/en.ts
+++ b/src/i18n/en.ts
@@ -284,6 +284,25 @@ export const en: Record<TranslationKey, string> = {
   "objinfo.kind.room": "Room",
   "objinfo.kind.extrudedSolid": "Extrusion",
   "objinfo.kind.column": "Column",
+  "objinfo.kind.roof": "Roof",
+  // ── Roof attributes (object info panel) ─────────────────────────────────
+  "objinfo.roof.section": "Roof",
+  "objinfo.roof.shape": "Roof shape",
+  "objinfo.roof.shape.flach": "Flat roof",
+  "objinfo.roof.shape.pult": "Mono-pitch roof",
+  "objinfo.roof.shape.sattel": "Gable roof",
+  "objinfo.roof.shape.walm": "Hip roof",
+  "objinfo.roof.shape.mansarde": "Mansard roof",
+  "objinfo.roof.shape.zelt": "Pyramid roof",
+  "objinfo.roof.ridgeAxis": "Ridge direction",
+  "objinfo.roof.ridgeAxis.x": "along X",
+  "objinfo.roof.ridgeAxis.y": "along Y",
+  "objinfo.roof.pitch": "Pitch (°)",
+  "objinfo.roof.pitchUpper": "Upper pitch (°)",
+  "objinfo.roof.overhang": "Overhang (m)",
+  "objinfo.roof.thickness": "Roof thickness (m)",
+  "objinfo.roof.ridgeHeight": "Ridge height",
+  "objinfo.roof.area": "Footprint area",
   // ── Column attributes (object info panel) ────────────────────────────────
   "objinfo.column.section": "Column",
   "objinfo.column.profile": "Profile",
diff --git a/src/panels/AttributesPanel.tsx b/src/panels/AttributesPanel.tsx
index c5868b7..be63416 100644
--- a/src/panels/AttributesPanel.tsx
+++ b/src/panels/AttributesPanel.tsx
@@ -36,6 +36,7 @@ import { ColorHexField } from "../ui/ColorHexField";
 import {
   WallSection,
   CeilingSection,
+  RoofSection,
   OpeningSection,
   StairSection,
   RoomSection,
@@ -314,6 +315,7 @@ export function AttributesPanel() {
           Darstellung + die Host-Handler. */}
       {sel.wall && <WallSection wall={sel.wall} host={host} />}
       {sel.ceiling && <CeilingSection ceiling={sel.ceiling} host={host} />}
+      {sel.roof && <RoofSection roof={sel.roof} host={host} />}
       {sel.opening && <OpeningSection opening={sel.opening} host={host} />}
       {sel.stair && <StairSection stair={sel.stair} host={host} />}
       {sel.room && <RoomSection room={sel.room} roomId={sel.id} host={host} />}
diff --git a/src/panels/ObjectInfoPanel.tsx b/src/panels/ObjectInfoPanel.tsx
index 8b96e15..86c1672 100644
--- a/src/panels/ObjectInfoPanel.tsx
+++ b/src/panels/ObjectInfoPanel.tsx
@@ -16,8 +16,10 @@
 
 import { useState } from "react";
 import { t } from "../i18n";
+import type { TranslationKey } from "../i18n";
 import { formatM } from "../model/types";
 import type {
+  RoofShape,
   SiaCategory,
   SliceTermination,
   StairShape,
@@ -32,6 +34,7 @@ import type {
   ColumnInfo,
   ExtrudedSolidInfo,
   OpeningInfo,
+  RoofInfo,
   RoomInfo,
   StairInfo,
   WallInfo,
@@ -431,6 +434,107 @@ export function ColumnSection({
 // ── Treppen-Attribut-Abschnitt ───────────────────────────────────────────────
 // Grundform (gerade/L/Wendel), Laufbreite, Stufenanzahl, Steighöhe (+ abgeleitete
 // Steigungshöhe/Auftrittstiefe), Laufrichtung; Referenzgeschoss + UK/OK read-only.
+/** Dach-Abschnitt: Form, Neigung(en), Überstand, Firstrichtung, Dicke. */
+export function RoofSection({
+  roof,
+  host,
+}: {
+  roof: RoofInfo;
+  host: ReturnType<typeof usePanelHost>;
+}) {
+  const numField = (
+    labelKey: TranslationKey,
+    value: number,
+    step: number,
+    apply: (v: number) => void,
+  ) => (
+    <div className="objinfo-field">
+      <span className="objinfo-flabel">{t(labelKey)}</span>
+      <input
+        type="number"
+        className="objinfo-text"
+        step={step}
+        value={Number(value.toFixed(2))}
+        onChange={(e) => {
+          const v = Number(e.target.value);
+          if (Number.isFinite(v)) apply(v);
+        }}
+        title={t(labelKey)}
+      />
+    </div>
+  );
+  return (
+    <>
+      <div className="objinfo-sep" />
+      <div className="objinfo-section-label">{t("objinfo.roof.section")}</div>
+
+      {/* Dachform. */}
+      <div className="objinfo-field">
+        <span className="objinfo-flabel">{t("objinfo.roof.shape")}</span>
+        <Dropdown
+          value={roof.shape}
+          onChange={(v) => host.onSetRoofPatch({ shape: v as RoofShape })}
+          options={[
+            { value: "flach", label: t("objinfo.roof.shape.flach") },
+            { value: "pult", label: t("objinfo.roof.shape.pult") },
+            { value: "sattel", label: t("objinfo.roof.shape.sattel") },
+            { value: "walm", label: t("objinfo.roof.shape.walm") },
+            { value: "mansarde", label: t("objinfo.roof.shape.mansarde") },
+            { value: "zelt", label: t("objinfo.roof.shape.zelt") },
+          ]}
+          title={t("objinfo.roof.shape")}
+          width={130}
+        />
+      </div>
+
+      {/* Firstrichtung (X/Y) — nur bei Formen mit First relevant. */}
+      {roof.shape !== "flach" && roof.shape !== "zelt" && (
+        <div className="objinfo-field">
+          <span className="objinfo-flabel">{t("objinfo.roof.ridgeAxis")}</span>
+          <Dropdown
+            value={roof.ridgeAxis}
+            onChange={(v) => host.onSetRoofPatch({ ridgeAxis: v as "x" | "y" })}
+            options={[
+              { value: "x", label: t("objinfo.roof.ridgeAxis.x") },
+              { value: "y", label: t("objinfo.roof.ridgeAxis.y") },
+            ]}
+            title={t("objinfo.roof.ridgeAxis")}
+            width={130}
+          />
+        </div>
+      )}
+
+      {/* Neigung(en) — Flachdach hat keine. */}
+      {roof.shape !== "flach" &&
+        numField("objinfo.roof.pitch", roof.pitchDeg, 1, (v) =>
+          host.onSetRoofPatch({ pitchDeg: Math.max(0, Math.min(85, v)) }),
+        )}
+      {roof.shape === "mansarde" &&
+        numField("objinfo.roof.pitchUpper", roof.pitchUpperDeg ?? roof.pitchDeg / 2, 1, (v) =>
+          host.onSetRoofPatch({ pitchUpperDeg: Math.max(0, Math.min(85, v)) }),
+        )}
+
+      {/* Überstand + Dicke (Meter). */}
+      {numField("objinfo.roof.overhang", roof.overhang, 0.05, (v) =>
+        host.onSetRoofPatch({ overhang: Math.max(0, v) }),
+      )}
+      {numField("objinfo.roof.thickness", roof.thickness, 0.02, (v) =>
+        host.onSetRoofPatch({ thickness: Math.max(0.01, v) }),
+      )}
+
+      {/* Abgeleitete Werte (read-only). */}
+      <div className="objinfo-field">
+        <span className="objinfo-flabel">{t("objinfo.roof.ridgeHeight")}</span>
+        <span className="objinfo-fval">{formatM(roof.ridgeHeight)}</span>
+      </div>
+      <div className="objinfo-field">
+        <span className="objinfo-flabel">{t("objinfo.roof.area")}</span>
+        <span className="objinfo-fval">{roof.footprintArea.toFixed(2)} m²</span>
+      </div>
+    </>
+  );
+}
+
 export function StairSection({
   stair,
   host,
diff --git a/src/panels/host.ts b/src/panels/host.ts
index 556cdfc..63f8d0c 100644
--- a/src/panels/host.ts
+++ b/src/panels/host.ts
@@ -299,6 +299,11 @@ export interface PanelHostValue {
    * (Discoverability: von der gewählten Öffnung in den Typeditor springen).
    */
   onEditOpeningType: (kind: "door" | "window") => void;
+  /**
+   * Immutable Änderung von Dach-Attributen (Form/Neigung/Überstand/Firstrichtung/
+   * Dicke) — wirkt NUR auf das selektierte Dach.
+   */
+  onSetRoofPatch: (patch: Partial<import("../model/types").Roof>) => void;
 
   // ── Treppen-Attribute (Object-Info-Panel; nur die selektierte Treppe) ───
   /** Setzt die Grundform (gerade/L/Wendel). */
diff --git a/src/plan/PlanView.tsx b/src/plan/PlanView.tsx
index 27ad285..8c3a12e 100644
--- a/src/plan/PlanView.tsx
+++ b/src/plan/PlanView.tsx
@@ -192,6 +192,11 @@ export interface PlanSelection {
    * traf und KEIN Element höherer Priorität (Öffnung/Wand); sonst `null`.
    */
   columnId: string | null;
+  /**
+   * ID des getroffenen Dachs (Traufe-Fläche), wenn der Klick es traf und KEIN
+   * Element höherer Priorität (alle anderen gehen vor); sonst `null`.
+   */
+  roofId: string | null;
   /**
    * War beim Klick Shift gedrückt? Dann ERWEITERT der Aufrufer (App) die
    * Auswahl um das getroffene Element (bzw. schaltet es ab/zu), statt sie zu
@@ -985,6 +990,20 @@ export const PlanView = forwardRef<PlanViewHandle, PlanViewProps>(
     return null;
   };
 
+  // Getroffenes Dach: das unsichtbare Traufe-Pick-Polygon per Punkt-in-Polygon
+  // (die sichtbaren Dachlinien allein wären schwer exakt zu treffen).
+  const pickRoof = (clientX: number, clientY: number): string | null => {
+    const v = clientToView(clientX, clientY, view);
+    const m = viewToModel(v.x, v.y);
+    for (let i = plan.primitives.length - 1; i >= 0; i--) {
+      const p = plan.primitives[i];
+      if (p.kind === "polygon" && p.roofId && pointInPolygon(m, p.pts)) {
+        return p.roofId;
+      }
+    }
+    return null;
+  };
+
   // Getroffener extrudierter Körper (truck-Integration): der Footprint-Umriss
   // ist ein reiner Haarlinien-Umriss (fill:"none"), aber per Punkt-in-Polygon
   // trotzdem als FLÄCHE anklickbar (analog Raum, nicht nur auf der Linie).
@@ -1536,11 +1555,17 @@ export const PlanView = forwardRef<PlanViewHandle, PlanViewProps>(
           openingId || wallId || columnId || drawingId || extrudedSolidId || ceilingId
             ? null
             : pickStair(e.clientX, e.clientY);
-        // Raum als letzte Priorität: die Raum-Fläche liegt UNTER allem anderen.
+        // Raum als vorletzte Priorität: die Raum-Fläche liegt UNTER allem anderen.
         const roomId =
           openingId || wallId || columnId || drawingId || extrudedSolidId || ceilingId || stairId
             ? null
             : pickRoom(e.clientX, e.clientY);
+        // Dach als LETZTE Priorität: die Traufe-Fläche deckt den ganzen Grundriss
+        // ab, daher erst wählen, wenn wirklich nichts anderes getroffen wurde.
+        const roofId =
+          openingId || wallId || columnId || drawingId || extrudedSolidId || ceilingId || stairId || roomId
+            ? null
+            : pickRoof(e.clientX, e.clientY);
         onSelect({
           model: viewToModel(v.x, v.y),
           hitIndex,
@@ -1552,6 +1577,7 @@ export const PlanView = forwardRef<PlanViewHandle, PlanViewProps>(
           roomId,
           extrudedSolidId,
           columnId,
+          roofId,
           shift: e.shiftKey,
         });
       }
diff --git a/src/plan/generatePlan.ts b/src/plan/generatePlan.ts
index 09a17a1..bf16853 100644
--- a/src/plan/generatePlan.ts
+++ b/src/plan/generatePlan.ts
@@ -258,6 +258,8 @@ export type Primitive =
        * (Poché) einer Stütze ist (für die Links-Klick-Auswahl der Fläche).
        */
       columnId?: string;
+      /** ID des Dachs (Roof), falls dieses (unsichtbare) Polygon der Traufe-Umriss ist (Auswahl). */
+      roofId?: string;
     }
   | {
       kind: "line";
@@ -2466,6 +2468,23 @@ function addRoof(
   const stroke = roof.color ?? category?.color ?? POCHE_STROKE;
   const geo = roofGeometry(roof, 0);
 
+  // Unsichtbares Pick-Polygon über der Traufe-Fläche — macht das Dach über die
+  // ganze Fläche per Links-Klick selektierbar (die Dachlinien allein wären
+  // schwer exakt zu treffen). fill/stroke "none" ⇒ zeichnet nichts; PlanView
+  // testet nur die `pts` (Punkt-in-Polygon), analog Öffnung/Decke.
+  if (geo.eaves.length >= 3) {
+    out.push({
+      kind: "polygon",
+      pts: geo.eaves,
+      fill: "none",
+      stroke: "none",
+      strokeWidthMm: 0,
+      hatch: NO_HATCH,
+      greyed,
+      roofId: roof.id,
+    });
+  }
+
   const n = geo.eaves.length;
   for (let i = 0; i < n; i++) {
     out.push({
diff --git a/src/state/projectSlice.ts b/src/state/projectSlice.ts
index 7227aa6..3e703a8 100644
--- a/src/state/projectSlice.ts
+++ b/src/state/projectSlice.ts
@@ -235,6 +235,12 @@ export interface ProjectSlice {
     patch: Partial<import("../model/types").Opening>,
   ) => void;
 
+  /** Immutable Änderung eines Dachs (Form/Neigung/Überstand/Firstrichtung/Dicke). */
+  updateRoof: (
+    id: string,
+    patch: Partial<import("../model/types").Roof>,
+  ) => void;
+
   // ── Treppen-Editieren ──────────────────────────────────────────────────────
   /** Verschiebt eine Treppe (Antritt) um `delta`. */
   moveStairBy: (stairId: string, delta: Vec2) => void;
@@ -913,6 +919,13 @@ export function createProjectSlice(
         openings: (p.openings ?? []).map((o) => (o.id === id ? { ...o, ...patch } : o)),
       })),
 
+    // ── Dach-Editieren ─────────────────────────────────────────────────────
+    updateRoof: (id, patch) =>
+      setProject((p) => ({
+        ...p,
+        roofs: (p.roofs ?? []).map((r) => (r.id === id ? { ...r, ...patch } : r)),
+      })),
+
     // ── Treppen-Editieren ──────────────────────────────────────────────────
     // (coalesceKey: siehe Kommentar bei moveGripOf.)
     moveStairBy: (stairId, delta) =>
diff --git a/src/state/roofSelection.test.ts b/src/state/roofSelection.test.ts
new file mode 100644
index 0000000..5c52284
--- /dev/null
+++ b/src/state/roofSelection.test.ts
@@ -0,0 +1,54 @@
+// Dach-Auswahl: deriveSelection liefert für ein selektiertes Dach eine
+// Roof-Selection mit den erwarteten Attributen (Form/Neigung/Firsthöhe/Fläche).
+
+import { describe, it, expect } from "vitest";
+import { deriveSelection } from "./selectionInfo";
+import type { Project, Roof } from "../model/types";
+
+const roof: Roof = {
+  id: "RF1",
+  type: "roof",
+  floorId: "eg",
+  categoryCode: "31",
+  outline: [
+    { x: 0, y: 0 },
+    { x: 6, y: 0 },
+    { x: 6, y: 4 },
+    { x: 0, y: 4 },
+  ],
+  shape: "sattel",
+  pitchDeg: 45,
+  overhang: 0,
+  ridgeAxis: "x",
+  thickness: 0.2,
+};
+
+const project = {
+  id: "p",
+  name: "T",
+  layers: [{ code: "31", name: "Dächer", color: "#7a4a3a", lw: 0.35, visible: true, locked: false }],
+  drawingLevels: [
+    { id: "eg", name: "EG", kind: "floor", visible: true, locked: false, floorHeight: 2.6, baseElevation: 0 },
+  ],
+  walls: [],
+  drawings2d: [],
+  roofs: [roof],
+} as unknown as Project;
+
+describe("deriveSelection — Dach", () => {
+  it("liefert eine Roof-Selection mit Form + abgeleiteten Werten", () => {
+    const sel = deriveSelection(project, [], null, null, null, null, null, null, null, "RF1");
+    expect(sel?.kind).toBe("roof");
+    expect(sel?.roof?.shape).toBe("sattel");
+    expect(sel?.roof?.pitchDeg).toBe(45);
+    // Firsthöhe = halbe Tiefe (2) · tan45 (1) = 2.
+    expect(sel?.roof?.ridgeHeight).toBeCloseTo(2, 6);
+    // Grundfläche 6×4 = 24.
+    expect(sel?.roof?.footprintArea).toBeCloseTo(24, 6);
+    expect(sel?.id).toBe("RF1");
+  });
+
+  it("ohne Dach-Auswahl kein Roof (null bei leerer Auswahl)", () => {
+    expect(deriveSelection(project, [], null)).toBeNull();
+  });
+});
diff --git a/src/state/selectionInfo.ts b/src/state/selectionInfo.ts
index 71667d3..a90731b 100644
--- a/src/state/selectionInfo.ts
+++ b/src/state/selectionInfo.ts
@@ -30,6 +30,8 @@ import type {
   LayerCategory,
   Opening,
   Project,
+  Roof,
+  RoofShape,
   Room,
   SiaCategory,
   SliceTermination,
@@ -49,6 +51,7 @@ import {
   wallVerticalExtent,
 } from "../model/wall";
 import { ceilingArea, outlineBBox } from "../geometry/ceiling";
+import { roofBBox, roofBaseElevation, roofGeometry } from "../geometry/roof";
 import { openingGapQuad, openingVerticalExtent } from "../geometry/opening";
 import { stairGeometry, stairBBox } from "../geometry/stair";
 
@@ -70,6 +73,25 @@ export interface FloorChoice {
   name: string;
 }
 
+/** Dach-Attribute fürs Objekt-Info-Panel (nur bei Auswahl genau eines Dachs). */
+export interface RoofInfo {
+  shape: RoofShape;
+  /** Hauptneigung (Grad). */
+  pitchDeg: number;
+  /** Obere Neigung (Grad) — nur Mansarde relevant. */
+  pitchUpperDeg?: number;
+  /** Dachüberstand an der Traufe (Meter). */
+  overhang: number;
+  /** Firstrichtung entlang X oder Y. */
+  ridgeAxis: "x" | "y";
+  /** Dachdicke (Meter). */
+  thickness: number;
+  /** Firsthöhe über der Traufe (Meter, abgeleitet). */
+  ridgeHeight: number;
+  /** Grundfläche des Umriss-Rechtecks (m², ohne Überstand). */
+  footprintArea: number;
+}
+
 /**
  * Eine wählbare Schichttrennlinie (Fuge zwischen zwei Schichten) als
  * Referenzlinie einer mehrschichtigen Wand. `offset` ist der fertige
@@ -299,7 +321,8 @@ export interface Selection {
     | "drawing2d"
     | "door"
     | "extrudedSolid"
-    | "column";
+    | "column"
+    | "roof";
   id: string;
   /** Grafik-Kategorie (Ebene) des Elements. */
   categoryCode: string;
@@ -357,6 +380,8 @@ export interface Selection {
   wall?: WallInfo;
   /** Decken-Attribute (nur bei `kind === "ceiling"`). */
   ceiling?: CeilingInfo;
+  /** Dach-Attribute (nur bei `kind === "roof"`). */
+  roof?: RoofInfo;
   /** Öffnungs-Attribute (nur bei `kind === "opening"`). */
   opening?: OpeningInfo;
   /** Treppen-Attribute (nur bei `kind === "stair"`). */
@@ -577,6 +602,37 @@ function ceilingSelection(project: Project, ceiling: Ceiling): Selection {
   };
 }
 
+/** Selektion für ein Dach ableiten (Farbe übersteuerbar, Strichstärke = Kategorie). */
+function roofSelection(project: Project, roof: Roof): Selection {
+  const cat = findCategory(project.layers, roof.categoryCode);
+  const color = roof.color ?? cat?.color ?? WALL_FALLBACK_COLOR;
+  const weightMm = cat?.lw ?? WALL_FALLBACK_MM;
+  const bb = roofBBox(roof.outline);
+  const eavesZ = roofBaseElevation(project, roof);
+  const g = roofGeometry(roof, eavesZ);
+  const footprintArea = Math.abs(bb.x1 - bb.x0) * Math.abs(bb.y1 - bb.y0);
+  const roofInfo: RoofInfo = {
+    shape: roof.shape,
+    pitchDeg: roof.pitchDeg,
+    pitchUpperDeg: roof.pitchUpperDeg,
+    overhang: roof.overhang,
+    ridgeAxis: roof.ridgeAxis,
+    thickness: roof.thickness,
+    ridgeHeight: g.ridgeHeight,
+    footprintArea,
+  };
+  return {
+    kind: "roof",
+    id: roof.id,
+    categoryCode: roof.categoryCode,
+    color,
+    weightMm,
+    closed: true,
+    bbox: { minX: bb.x0, minY: bb.y0, maxX: bb.x1, maxY: bb.y1 },
+    roof: roofInfo,
+  };
+}
+
 /** Selektion für eine Öffnung ableiten (Farbe übersteuerbar, Strichstärke = Kategorie). */
 function openingSelection(project: Project, o: Opening): Selection {
   const cat = findCategory(project.layers, o.categoryCode);
@@ -847,6 +903,7 @@ export function deriveSelection(
   selectedRoomId: string | null = null,
   selectedExtrudedSolidId: string | null = null,
   selectedColumnId: string | null = null,
+  selectedRoofId: string | null = null,
 ): Selection | null {
   if (selectedDrawingId) {
     const d = project.drawings2d.find((x) => x.id === selectedDrawingId);
@@ -873,6 +930,10 @@ export function deriveSelection(
     const c = (project.ceilings ?? []).find((x) => x.id === selectedCeilingId);
     return c ? ceilingSelection(project, c) : null;
   }
+  if (selectedRoofId) {
+    const r = (project.roofs ?? []).find((x) => x.id === selectedRoofId);
+    return r ? roofSelection(project, r) : null;
+  }
   if (selectedStairId) {
     const s = (project.stairs ?? []).find((x) => x.id === selectedStairId);
     return s ? stairSelection(project, s) : null;
diff --git a/src/state/selectionSlice.ts b/src/state/selectionSlice.ts
index 425da39..b7bfa4a 100644
--- a/src/state/selectionSlice.ts
+++ b/src/state/selectionSlice.ts
@@ -23,6 +23,8 @@ export interface SelectionSlice {
   selectedExtrudedSolidIds: string[];
   // Gewählte Stützen (Tragwerk) als MENGE von IDs — getrennt von den übrigen Kanälen.
   selectedColumnIds: string[];
+  // Gewählte Dächer als MENGE von IDs — getrennt von den übrigen Kanälen.
+  selectedRoofIds: string[];
 
   setSelectedWallIds: (ids: string[]) => void;
   setSelectedDrawingIds: (ids: string[]) => void;
@@ -32,7 +34,8 @@ export interface SelectionSlice {
   setSelectedRoomIds: (ids: string[]) => void;
   setSelectedExtrudedSolidIds: (ids: string[]) => void;
   setSelectedColumnIds: (ids: string[]) => void;
-  /** Auswahl (Wände + Decken + Öffnungen + Treppen + 2D-Elemente) leeren. */
+  setSelectedRoofIds: (ids: string[]) => void;
+  /** Auswahl (Wände + Decken + Öffnungen + Treppen + Dächer + 2D-Elemente) leeren. */
   clearSelection: () => void;
 }
 
@@ -49,6 +52,7 @@ export function createSelectionSlice(
     selectedRoomIds: [],
     selectedExtrudedSolidIds: [],
     selectedColumnIds: [],
+    selectedRoofIds: [],
     setSelectedWallIds: (ids) => set({ selectedWallIds: ids }),
     setSelectedDrawingIds: (ids) => set({ selectedDrawingIds: ids }),
     setSelectedCeilingIds: (ids) => set({ selectedCeilingIds: ids }),
@@ -57,6 +61,7 @@ export function createSelectionSlice(
     setSelectedRoomIds: (ids) => set({ selectedRoomIds: ids }),
     setSelectedExtrudedSolidIds: (ids) => set({ selectedExtrudedSolidIds: ids }),
     setSelectedColumnIds: (ids) => set({ selectedColumnIds: ids }),
+    setSelectedRoofIds: (ids) => set({ selectedRoofIds: ids }),
     clearSelection: () =>
       set({
         selectedWallIds: [],
@@ -67,6 +72,7 @@ export function createSelectionSlice(
         selectedRoomIds: [],
         selectedExtrudedSolidIds: [],
         selectedColumnIds: [],
+        selectedRoofIds: [],
       }),
   };
 }