diff --git a/icinga-build-upload-aptly b/icinga-build-upload-aptly
index 9097e9449e5e42b3b3a44ad31be836c65d72f200..a49b49178db300f459a977e3c9d3d8f092e5d681 100755
--- a/icinga-build-upload-aptly
+++ b/icinga-build-upload-aptly
@@ -95,6 +95,7 @@ parser.add_argument('--release', metavar='release', required=True,
 parser.add_argument('--repo', metavar='repo',
                     help='Specific repository name in aptly')
 parser.add_argument('--architectures', metavar='list',
+                    default=os.environ.get('ICINGA_BUILD_DEB_DEFAULT_ARCH', 'amd64'),
                     help=('Specify list of architectures to publish the repo with,'
                           'separated by comma (e.g. amd64,i386 or armhf)'))
 parser.add_argument('--insecure', action='store_true', help='Disable SSL verification')
@@ -143,6 +144,10 @@ if args.repo:
 if args.architectures:
     upload_meta['architectures'] = re.split(r'\s*,\s*', args.architectures)
 
+    # always add i386 if amd64 is base arch
+    if 'amd64' in upload_meta['architectures'] and not 'i386' in upload_meta['architectures']:
+        upload_meta['architectures'].append('i386')
+
 # uploading files
 upload_url = aptly_url('/files/' + upload_name)
 print "Uploading %d files to %s" % (len(files), upload_name)