diff --git a/Rakefile.rb b/Rakefile.rb
index 6ed6fc1..cebe9b2 100644
--- a/Rakefile.rb
+++ b/Rakefile.rb
@@ -12,9 +12,12 @@ require "yard"
 
 CLEAN.include 'build_tests_run'
 
-RSpec::Core::RakeTask.new(:spec)
+RSpec::Core::RakeTask.new(:spec) do |task|
+  task.rspec_opts = "--default-path spec"
+end
 
 RSpec::Core::RakeTask.new(:build_tests) do |task|
+  task.rspec_opts = "--default-path build_tests"
   task.pattern = "build_tests/*_spec.rb"
 end
 
diff --git a/build_tests/spec_helper.rb b/build_tests/spec_helper.rb
new file mode 100644
index 0000000..46086fe
--- /dev/null
+++ b/build_tests/spec_helper.rb
@@ -0,0 +1,8 @@
+require "simplecov"
+
+SimpleCov.start do
+  add_filter "/build_tests/"
+  command_name("build_tests")
+end
+
+require "rscons"
diff --git a/spec/spec_helper.rb b/spec/spec_helper.rb
index 78f39ad..dbc97ad 100644
--- a/spec/spec_helper.rb
+++ b/spec/spec_helper.rb
@@ -2,7 +2,6 @@ require "simplecov"
 
 SimpleCov.start do
   add_filter "/spec/"
-  add_filter "/build_tests/"
 end
 
 require "rscons"