diff --git a/src/util/skeleton-utils.js b/src/util/skeleton-utils.js
index 49cd1a7c..7bd773f6 100644
--- a/src/util/skeleton-utils.js
+++ b/src/util/skeleton-utils.js
@@ -802,6 +802,10 @@ const createInnerLinesFromSkeleton = (roofId, canvas, skeleton, textMode) => {
           const getAddLine = (p1, p2, stroke = '') => {
             movedLines.push({ index, p1, p2 })
 
+            const dx = Math.abs(p2.x - p1.x);
+            const dy = Math.abs(p2.y - p1.y);
+            const isDiagonal = dx > 0.5 && dy > 0.5; // x, y 변화가 모두 있으면 대각선
+
             //console.log("mergeLines:::::::", mergeLines);
             const line = new QLine([p1.x, p1.y, p2.x, p2.y], {
               parentId: roof.id,
@@ -818,6 +822,15 @@ const createInnerLinesFromSkeleton = (roofId, canvas, skeleton, textMode) => {
                 type: 'eaveHelpLine',
                 isStart: true,
                 pitch: wallLine.attributes.pitch,
+                actualSize: (isDiagonal) ? calcLineActualSize(
+                  {
+                    x1: p1.x,
+                    y1: p1.y,
+                    x2: p2.x,
+                    y2: p2.y
+                  },
+                getDegreeByChon(wallLine.attributes.pitch)
+                ) : calcLinePlaneSize({ x1: p1.x, y1: p1.y, x2: p2.x, y2: p2.y }),
               },
             })