diff --git a/platformio/package/manager/library.py b/platformio/package/manager/library.py
index 3ce2a1fa..e67a5110 100644
--- a/platformio/package/manager/library.py
+++ b/platformio/package/manager/library.py
@@ -21,13 +21,15 @@ from platformio.package.exception import (
 )
 from platformio.package.manager.base import BasePackageManager
 from platformio.package.meta import PackageItem, PackageSpec, PackageType
-from platformio.project.helpers import get_project_global_lib_dir
+from platformio.project.config import ProjectConfig
 
 
 class LibraryPackageManager(BasePackageManager):  # pylint: disable=too-many-ancestors
     def __init__(self, package_dir=None):
         super(LibraryPackageManager, self).__init__(
-            PackageType.LIBRARY, package_dir or get_project_global_lib_dir()
+            PackageType.LIBRARY,
+            package_dir
+            or ProjectConfig.get_instance().get("platformio", "globallib_dir"),
         )
 
     @property
diff --git a/platformio/project/helpers.py b/platformio/project/helpers.py
index 9e995b7b..4cf66470 100644
--- a/platformio/project/helpers.py
+++ b/platformio/project/helpers.py
@@ -43,6 +43,23 @@ def find_project_dir_above(path):
     return None
 
 
+def get_project_all_lib_dirs():
+    """Used by platformio-node-helpers.project.observer.fetchLibDirs"""
+    config = ProjectConfig.get_instance()
+    libdeps_dir = config.get("platformio", "libdeps_dir")
+    result = [
+        config.get("platformio", "globallib_dir"),
+        config.get("platformio", "lib_dir"),
+        libdeps_dir,
+    ]
+    if not os.path.isdir(libdeps_dir):
+        return result
+    for d in os.listdir(libdeps_dir):
+        if os.path.isdir(os.path.join(libdeps_dir, d)):
+            result.append(os.path.join(libdeps_dir, d))
+    return result
+
+
 def get_project_cache_dir():
     """Deprecated, use ProjectConfig.get("platformio", "cache_dir") instead"""
     return ProjectConfig.get_instance().get("platformio", "cache_dir")
diff --git a/platformio/project/options.py b/platformio/project/options.py
index c8a46da9..5314da6e 100644
--- a/platformio/project/options.py
+++ b/platformio/project/options.py
@@ -115,9 +115,9 @@ def validate_dir(path):
 
 
 def validate_core_dir(path):
-    default = ProjectOptions["platformio.core_dir"].default
+    default_dir = ProjectOptions["platformio.core_dir"].default
     win_core_dir = None
-    if IS_WINDOWS and path == default:
+    if IS_WINDOWS and path == default_dir:
         win_core_dir = os.path.splitdrive(path)[0] + "\\.platformio"
         if os.path.isdir(win_core_dir):
             path = win_core_dir
diff --git a/tests/test_projectconf.py b/tests/test_projectconf.py
index b1859c5d..2408463a 100644
--- a/tests/test_projectconf.py
+++ b/tests/test_projectconf.py
@@ -15,6 +15,7 @@
 # pylint: disable=redefined-outer-name
 
 import os
+import sys
 
 import pytest
 
@@ -521,3 +522,36 @@ def test_dump(tmpdir_factory):
             ],
         ),
     ]
+
+
+@pytest.mark.skipif(sys.platform != "win32", reason="runs only on windows")
+def test_win_core_root_dir(tmpdir_factory):
+    try:
+        win_core_root_dir = os.path.splitdrive(fs.expanduser("~"))[0] + "\\.platformio"
+        remove_dir_at_exit = False
+        if not os.path.isdir(win_core_root_dir):
+            remove_dir_at_exit = True
+            os.makedirs(win_core_root_dir)
+
+        # Default config
+        config = ProjectConfig()
+        assert config.get("platformio", "core_dir") == win_core_root_dir
+
+        # Override in config
+        tmpdir = tmpdir_factory.mktemp("project")
+        tmpdir.join("platformio.ini").write(
+            """
+[platformio]
+core_dir = ~/.pio
+        """
+        )
+        config = ProjectConfig(tmpdir.join("platformio.ini").strpath)
+        assert config.get("platformio", "core_dir") != win_core_root_dir
+        assert config.get("platformio", "core_dir") == os.path.realpath(
+            fs.expanduser("~/.pio")
+        )
+
+        if remove_dir_at_exit:
+            fs.rmtree(win_core_root_dir)
+    except PermissionError:
+        pass