diff --git a/test/provider/immowelt.test.js b/test/provider/immowelt.test.js
index b3acd7f..1c1a07c 100644
--- a/test/provider/immowelt.test.js
+++ b/test/provider/immowelt.test.js
@@ -32,13 +32,13 @@ describe('#immowelt testsuite()', () => {
           /** check the actual structure **/
           expect(notify.id).to.be.a('string');
           expect(notify.price).to.be.a('string');
-          expect(notify.size).to.be.a('string');
           expect(notify.title).to.be.a('string');
+
           expect(notify.link).to.be.a('string');
           expect(notify.address).to.be.a('string');
 
           /** check the values if possible **/
-          if (notify.size.trim().toLowerCase() !== 'k.a.') {
+          if (notify.size != null && notify.size.trim().toLowerCase() !== 'k.a.') {
             expect(notify.size).that.does.include('m²');
           }
           expect(notify.title).to.be.not.empty;