diff --git a/lib/capybara-screenshot.rb b/lib/capybara-screenshot.rb
index 0a94883..db987ba 100644
--- a/lib/capybara-screenshot.rb
+++ b/lib/capybara-screenshot.rb
@@ -52,7 +52,7 @@ def self.filename_prefix_for(test_type, test)
     end
 
     def self.capybara_root
-      @capybara_root ||= if defined?(::Rails)
+      @capybara_root ||= if defined?(::Rails) && Rails.root.present?
         ::Rails.root.join capybara_tmp_path
       elsif defined?(Padrino)
         File.expand_path(capybara_tmp_path, Padrino.root)