diff --git a/cara/apps/calculator/__init__.py b/cara/apps/calculator/__init__.py
index 407382e3..c5b50385 100644
--- a/cara/apps/calculator/__init__.py
+++ b/cara/apps/calculator/__init__.py
@@ -229,7 +229,7 @@ def make_app(
     calculator_templates = Path(__file__).parent / "templates"
     templates_directories = [cara_templates, calculator_templates]
     if theme_dir:
-        templates_directories.insert(0, theme_dir / 'templates')
+        templates_directories.insert(0, theme_dir)
     loader = jinja2.FileSystemLoader([str(path) for path in templates_directories])
     template_environment = jinja2.Environment(
         loader=loader,
diff --git a/cara/apps/calculator/__main__.py b/cara/apps/calculator/__main__.py
index 7ec61206..7ec8b69a 100644
--- a/cara/apps/calculator/__main__.py
+++ b/cara/apps/calculator/__main__.py
@@ -36,7 +36,6 @@ def main():
     if theme_dir is not None:
         theme_dir = Path(theme_dir).absolute()
         assert theme_dir.exists()
-        assert (theme_dir / 'templates').exists()
     app = make_app(debug=args.no_debug, calculator_prefix=args.prefix, theme_dir=theme_dir)
     app.listen(args.port)
     IOLoop.instance().start()
diff --git a/cara/apps/calculator/templates/base/calculator.form.html.j2 b/cara/apps/templates/base/calculator.form.html.j2
similarity index 100%
rename from cara/apps/calculator/templates/base/calculator.form.html.j2
rename to cara/apps/templates/base/calculator.form.html.j2
diff --git a/cara/apps/calculator/templates/base/calculator.report.html.j2 b/cara/apps/templates/base/calculator.report.html.j2
similarity index 100%
rename from cara/apps/calculator/templates/base/calculator.report.html.j2
rename to cara/apps/templates/base/calculator.report.html.j2
diff --git a/cara/apps/calculator/templates/base/userguide.html.j2 b/cara/apps/templates/base/userguide.html.j2
similarity index 100%
rename from cara/apps/calculator/templates/base/userguide.html.j2
rename to cara/apps/templates/base/userguide.html.j2
diff --git a/cara/apps/calculator/templates/calculator.form.html.j2 b/cara/apps/templates/calculator.form.html.j2
similarity index 100%
rename from cara/apps/calculator/templates/calculator.form.html.j2
rename to cara/apps/templates/calculator.form.html.j2
diff --git a/cara/apps/calculator/templates/calculator.report.html.j2 b/cara/apps/templates/calculator.report.html.j2
similarity index 100%
rename from cara/apps/calculator/templates/calculator.report.html.j2
rename to cara/apps/templates/calculator.report.html.j2
diff --git a/cara/apps/themes/cern/templates/calculator.form.html.j2 b/cara/apps/templates/cern/calculator.form.html.j2
similarity index 100%
rename from cara/apps/themes/cern/templates/calculator.form.html.j2
rename to cara/apps/templates/cern/calculator.form.html.j2
diff --git a/cara/apps/themes/cern/templates/calculator.report.html.j2 b/cara/apps/templates/cern/calculator.report.html.j2
similarity index 100%
rename from cara/apps/themes/cern/templates/calculator.report.html.j2
rename to cara/apps/templates/cern/calculator.report.html.j2
diff --git a/cara/apps/themes/cern/templates/index.html.j2 b/cara/apps/templates/cern/index.html.j2
similarity index 100%
rename from cara/apps/themes/cern/templates/index.html.j2
rename to cara/apps/templates/cern/index.html.j2
diff --git a/cara/apps/themes/cern/templates/layout.html.j2 b/cara/apps/templates/cern/layout.html.j2
similarity index 100%
rename from cara/apps/themes/cern/templates/layout.html.j2
rename to cara/apps/templates/cern/layout.html.j2
diff --git a/cara/apps/themes/cern/templates/userguide.html.j2 b/cara/apps/templates/cern/userguide.html.j2
similarity index 100%
rename from cara/apps/themes/cern/templates/userguide.html.j2
rename to cara/apps/templates/cern/userguide.html.j2
diff --git a/cara/apps/calculator/templates/userguide.html.j2 b/cara/apps/templates/userguide.html.j2
similarity index 100%
rename from cara/apps/calculator/templates/userguide.html.j2
rename to cara/apps/templates/userguide.html.j2