diff --git a/projects/angular-split/src/lib/directive/split-area.directive.ts b/projects/angular-split/src/lib/directive/split-area.directive.ts
index c62bd34b..31bbb47c 100644
--- a/projects/angular-split/src/lib/directive/split-area.directive.ts
+++ b/projects/angular-split/src/lib/directive/split-area.directive.ts
@@ -21,7 +21,7 @@ export class SplitAreaDirective implements OnInit, OnDestroy {
     return this._order
   }
 
-  private _size: IAreaSize = null
+  private _size: IAreaSize = '*'
 
   @Input() set size(v: IAreaSize | `${number}` | null | undefined) {
     this._size = getInputPositiveNumber(v, '*')