diff --git a/pisi/operations/build.py b/pisi/operations/build.py
index 27b8ec92..d3cdb5de 100644
--- a/pisi/operations/build.py
+++ b/pisi/operations/build.py
@@ -613,7 +613,7 @@ class Builder:
         for patch in self.spec.source.patches:
             patchFile = pisi.util.join_path(files_dir, patch.filename)
             relativePath = patch.filename
-            reverseApply = patch.reverse.lower() == "true"
+            reverseApply = patch.reverse and patch.reverse.lower() == "true"
             if patch.compressionType:
                 patchFile = pisi.util.uncompress(patchFile,
                                             compressType=patch.compressionType,