diff --git a/packages/@ngtools/webpack/src/compiler_host.ts b/packages/@ngtools/webpack/src/compiler_host.ts
index 7c56c50fcfe4..e0b4fc05ce7f 100644
--- a/packages/@ngtools/webpack/src/compiler_host.ts
+++ b/packages/@ngtools/webpack/src/compiler_host.ts
@@ -188,7 +188,8 @@ export class WebpackCompilerHost implements ts.CompilerHost {
 
   invalidate(fileName: string): void {
     fileName = this._resolve(fileName);
-    if (fileName in this._files) {
+    const result = this.readFile(fileName);
+    if (!result) {
       this._files[fileName] = null;
       this._changedFiles[fileName] = true;
     }