diff --git a/kiwi/builder/disk.py b/kiwi/builder/disk.py
index 92a7a94ccb2..96dfc8370d7 100644
--- a/kiwi/builder/disk.py
+++ b/kiwi/builder/disk.py
@@ -18,7 +18,7 @@
 import os
 import logging
 from typing import (
-    Dict, List, Optional, Tuple, Any
+    Dict, List, Optional, Tuple, Union
 )
 
 # project
@@ -49,6 +49,7 @@
 from kiwi.filesystem import FileSystem
 from kiwi.filesystem.squashfs import FileSystemSquashFs
 from kiwi.volume_manager import VolumeManager
+from kiwi.volume_manager.base import VolumeManagerBase
 from kiwi.command import Command
 from kiwi.system.setup import SystemSetup
 from kiwi.builder.install import InstallImageBuilder
@@ -234,7 +235,8 @@ def create_disk(self) -> Result:
         # an instance of a class with the sync_data capability
         # representing the entire image system except for the boot/ area
         # which could live on another part of the disk
-        system: Any = None
+        system: Union[FileSystemBase, VolumeManagerBase] = \
+            FileSystemBase(DeviceProvider())
 
         # an instance of a class with the sync_data capability
         # representing the boot/ area of the disk if not part of
@@ -644,7 +646,7 @@ def _build_main_system(
         self,
         device_map: Dict,
         disk: Disk,
-        system: Any,
+        system: Union[FileSystemBase, VolumeManagerBase],
         system_boot: Optional[FileSystemBase],
         system_efi: Optional[FileSystemBase],
         system_spare: Optional[FileSystemBase],
@@ -1136,13 +1138,15 @@ def _write_crypttab_to_system_image(
             )
 
     def _write_generic_fstab_to_system_image(
-        self, device_map: Dict, system: Any
+        self, device_map: Dict,
+        system: Union[FileSystemBase, VolumeManagerBase]
     ) -> None:
         log.info('Creating generic system etc/fstab')
         self._write_generic_fstab(device_map, self.system_setup, system)
 
     def _write_generic_fstab_to_boot_image(
-        self, device_map: Dict, system: Any
+        self, device_map: Dict,
+        system: Union[FileSystemBase, VolumeManagerBase]
     ) -> None:
         if self.initrd_system == 'kiwi':
             log.info('Creating generic boot image etc/fstab')
@@ -1152,7 +1156,7 @@ def _write_generic_fstab_to_boot_image(
 
     def _write_generic_fstab(
         self, device_map: Dict, setup: SystemSetup,
-        system: Any
+        system: Union[FileSystemBase, VolumeManagerBase]
     ) -> None:
         root_is_snapshot = \
             self.xml_state.build_type.get_btrfs_root_is_snapshot()
@@ -1291,7 +1295,8 @@ def _write_recovery_metadata_to_boot_image(self) -> None:
             )
 
     def _write_bootloader_meta_data_to_system_image(
-        self, device_map: Dict, disk: Disk, system: Any
+        self, device_map: Dict, disk: Disk,
+        system: Union[FileSystemBase, VolumeManagerBase]
     ) -> None:
         if self.bootloader != 'custom':
             log.info('Creating %s bootloader configuration', self.bootloader)
@@ -1353,7 +1358,8 @@ def _write_bootloader_meta_data_to_system_image(
         )
 
     def _sync_system_to_image(
-        self, device_map: Dict, system: Any,
+        self, device_map: Dict,
+        system: Union[FileSystemBase, VolumeManagerBase],
         system_boot: Optional[FileSystemBase],
         system_efi: Optional[FileSystemBase],
         system_spare: Optional[FileSystemBase],
@@ -1551,7 +1557,8 @@ def _sync_system_to_image(
             self.integrity_root.write_integrity_metadata()
 
     def _install_bootloader(
-        self, device_map: Dict, disk, system: Any
+        self, device_map: Dict, disk,
+        system: Union[FileSystemBase, VolumeManagerBase]
     ) -> None:
         root_device = device_map['root']
         boot_device = root_device
@@ -1632,7 +1639,9 @@ def _install_bootloader(
             self.diskname, boot_device.get_device()
         )
 
-    def _setup_property_root_is_readonly_snapshot(self, system: Any) -> None:
+    def _setup_property_root_is_readonly_snapshot(
+        self, system: Union[FileSystemBase, VolumeManagerBase]
+    ) -> None:
         if self.volume_manager_name:
             root_is_snapshot = \
                 self.xml_state.build_type.get_btrfs_root_is_snapshot()
diff --git a/kiwi/filesystem/base.py b/kiwi/filesystem/base.py
index eea08fb8592..2a497fa3c60 100644
--- a/kiwi/filesystem/base.py
+++ b/kiwi/filesystem/base.py
@@ -265,6 +265,56 @@ def umount(self) -> None:
             log.info('umount %s instance', type(self).__name__)
             self.filesystem_mount.umount()
 
+    def umount_volumes(self) -> None:
+        """
+        Consistency layer with regards to VolumeManager classes
+
+        Invokes umount
+        """
+        self.umount()
+
+    def mount_volumes(self) -> None:
+        """
+        Consistency layer with regards to VolumeManager classes
+
+        Invokes mount
+        """
+        self.mount()
+
+    def get_volumes(self) -> Dict:
+        """
+        Consistency layer with regards to VolumeManager classes
+
+        Raises
+        """
+        raise NotImplementedError
+
+    def get_root_volume_name(self) -> None:
+        """
+        Consistency layer with regards to VolumeManager classes
+
+        Raises
+        """
+        raise NotImplementedError
+
+    def get_fstab(
+        self, persistency_type: str = 'by-label', filesystem_name: str = ''
+    ) -> List[str]:
+        """
+        Consistency layer with regards to VolumeManager classes
+
+        Raises
+        """
+        raise NotImplementedError
+
+    def set_property_readonly_root(self) -> None:
+        """
+        Consistency layer with regards to VolumeManager classes
+
+        Raises
+        """
+        raise NotImplementedError
+
     def _map_size(self, size: float, from_unit: str, to_unit: str) -> float:
         """
         Return byte size value for given size and unit
diff --git a/kiwi/volume_manager/base.py b/kiwi/volume_manager/base.py
index 67cbdf319a4..f1e6dd9f354 100644
--- a/kiwi/volume_manager/base.py
+++ b/kiwi/volume_manager/base.py
@@ -187,6 +187,22 @@ def umount_volumes(self):
         """
         raise NotImplementedError
 
+    def umount(self):
+        """
+        Consistency layer with regards to FileSystem classes
+
+        Invokes umount_volumes
+        """
+        self.umount_volumes()
+
+    def mount(self):
+        """
+        Consistency layer with regards to FileSystem classes
+
+        Invokes mount_volumes
+        """
+        self.mount_volumes()
+
     def is_loop(self):
         """
         Check if storage provider is loop based
diff --git a/kiwi/volume_manager/btrfs.py b/kiwi/volume_manager/btrfs.py
index d8ad12e2a70..e504373cc94 100644
--- a/kiwi/volume_manager/btrfs.py
+++ b/kiwi/volume_manager/btrfs.py
@@ -269,7 +269,9 @@ def create_volumes(self, filesystem_name):
                     volume_mount
                 )
 
-    def get_fstab(self, persistency_type='by-label', filesystem_name=None):
+    def get_fstab(
+        self, persistency_type: str = 'by-label', filesystem_name: str = ''
+    ) -> List[str]:
         """
         Implements creation of the fstab entries. The method
         returns a list of fstab compatible entries
diff --git a/kiwi/volume_manager/lvm.py b/kiwi/volume_manager/lvm.py
index ab88349971f..aa97b6a0b55 100644
--- a/kiwi/volume_manager/lvm.py
+++ b/kiwi/volume_manager/lvm.py
@@ -17,6 +17,9 @@
 #
 import os
 import logging
+from typing import (
+    Dict, List
+)
 
 # project
 import kiwi.defaults as defaults
@@ -228,7 +231,9 @@ def create_volumes(self, filesystem_name):
         for mount_path in Path.sort_by_hierarchy(sorted(volume_paths.keys())):
             self.mount_list.append(volume_paths[mount_path])
 
-    def get_fstab(self, persistency_type, filesystem_name):
+    def get_fstab(
+        self, persistency_type: str = 'by-label', filesystem_name: str = ''
+    ) -> List[str]:
         """
         Implements creation of the fstab entries. The method
         returns a list of fstab compatible entries
@@ -266,7 +271,7 @@ def get_fstab(self, persistency_type, filesystem_name):
 
         return fstab_entries
 
-    def get_volumes(self):
+    def get_volumes(self) -> Dict:
         """
         Return dict of volumes
 
diff --git a/test/unit/filesystem/base_test.py b/test/unit/filesystem/base_test.py
index eb89c364f85..3f1698a8ea6 100644
--- a/test/unit/filesystem/base_test.py
+++ b/test/unit/filesystem/base_test.py
@@ -111,12 +111,40 @@ def test_umount(self):
         self.fsbase.umount()
         mount.umount.assert_called_once_with()
 
+    def test_umount_volumes(self):
+        mount = Mock()
+        self.fsbase.filesystem_mount = mount
+        self.fsbase.umount_volumes()
+        mount.umount.assert_called_once_with()
+
     def test_mount(self):
         mount = Mock()
         self.fsbase.filesystem_mount = mount
         self.fsbase.mount()
         mount.mount.assert_called_once_with([])
 
+    def test_mount_volumes(self):
+        mount = Mock()
+        self.fsbase.filesystem_mount = mount
+        self.fsbase.mount_volumes()
+        mount.mount.assert_called_once_with([])
+
+    def test_get_volumes(self):
+        with raises(NotImplementedError):
+            self.fsbase.get_volumes()
+
+    def test_get_root_volume_name(self):
+        with raises(NotImplementedError):
+            self.fsbase.get_root_volume_name()
+
+    def test_get_fstab(self):
+        with raises(NotImplementedError):
+            self.fsbase.get_fstab()
+
+    def test_set_property_readonly_root(self):
+        with raises(NotImplementedError):
+            self.fsbase.set_property_readonly_root()
+
     def test_fs_size(self):
         # size of 100k must be 100k (default unit)
         assert self.fsbase._fs_size(100) == '100'
diff --git a/test/unit/volume_manager/base_test.py b/test/unit/volume_manager/base_test.py
index aaba787a34f..9aec10e4423 100644
--- a/test/unit/volume_manager/base_test.py
+++ b/test/unit/volume_manager/base_test.py
@@ -213,10 +213,18 @@ def test_mount_volumes(self):
         with raises(NotImplementedError):
             self.volume_manager.mount_volumes()
 
+    def test_mount(self):
+        with raises(NotImplementedError):
+            self.volume_manager.mount()
+
     def test_umount_volumes(self):
         with raises(NotImplementedError):
             self.volume_manager.umount_volumes()
 
+    def test_umount(self):
+        with raises(NotImplementedError):
+            self.volume_manager.umount()
+
     def test_get_volumes(self):
         with raises(NotImplementedError):
             self.volume_manager.get_volumes()