diff --git a/build-msvc.bat b/build-msvc.bat
index d733ff0..044ed6e 100755
--- a/build-msvc.bat
+++ b/build-msvc.bat
@@ -70,10 +70,21 @@ if %clean% == true (
     echo ------------------------
     echo  cleaning up old files
     echo ------------------------
-    rd /s /q "third_party\sgl"
     rd /s /q "third_party\vcpkg"
     for /d %%G in (".build*") do rd /s /q "%%~G"
     rd /s /q "Shipping"
+
+:: https://stackoverflow.com/questions/5626879/how-to-find-if-a-file-contains-a-given-string-using-windows-command-line
+    find /c "sgl" .gitmodules >NUL
+    if %errorlevel% equ 1 goto notfound
+    rd /s /q "third_party\sgl\install"
+    for /d %%G in ("third_party\sgl\.build*") do rd /s /q "%%~G"
+    goto done
+    :notfound
+    rd /s /q "third_party\sgl"
+    goto done
+    :done
+
     git submodule update --init --recursive
 )
 
diff --git a/build.sh b/build.sh
index b8c3d2c..2fb7e64 100755
--- a/build.sh
+++ b/build.sh
@@ -137,7 +137,12 @@ if [ $clean = true ]; then
     echo "------------------------"
     echo " cleaning up old files  "
     echo "------------------------"
-    rm -rf third_party/sgl/ third_party/vcpkg/ .build_release/ .build_debug/ Shipping/
+    rm -rf third_party/vcpkg/ .build_release/ .build_debug/ Shipping/
+    if grep -wq "sgl" .gitmodules; then
+        rm -rf third_party/sgl/install/ third_party/sgl/.build_release/ third_party/sgl/.build_debug/
+    else
+        rm -rf third_party/sgl/
+    fi
     git submodule update --init --recursive
 fi