diff --git a/src/term/border.rs b/src/term/border.rs
index f09a46a..1edbc5a 100644
--- a/src/term/border.rs
+++ b/src/term/border.rs
@@ -194,7 +194,7 @@ pub trait BorderStyle: Draw<Tui> + Copy {
         let area = to.area();
         let style = style.or_else(||self.style_vertical());
         let [x, x2, y, y2] = area.lrtb();
-        let h = y2 - y;
+        let h = y2.minus(y);
         if h > 1 {
             for y in y..y2.saturating_sub(1) {
                 to.blit(&Self::W, x, y, style);