On Windows 10, you can create "Simple (no resiliency)" storage spaces that allow you to create more efficient storage by using multiple physical disks instead of one.
The other advantage is that this type of storage can be expanded later if you need more space in the future.

Tutorial made on Windows 10 version 2104 and also tested with Windows 11 v21H2, 8.1 Pro and 8 Pro.

Note: optimizing the use of drives is only available from Windows 10.
This option allows you to force the distribution of data when adding a new physical disk to improve the performance of your storage space.
However, this option is not required to expand, although it is interesting (if it is available).

1. Create a simple storage space (RAID 0)
2. Add a physical disk to expand your storage pool
3. Increase the size of a single storage space (RAID 0)

1. Create a simple storage space (RAID 0)

When you want to create a simple storage, you select "Resilience type: Simple (no resiliency)" and click on the "Create storage space" button.
By default, the size indicated by Windows for this storage space and the size including resilience are the same since there is no fault tolerance (so no parity data).

To learn more about creating a "Simple (no resiliency)" type storage, refer to step "4.1. Create a simple storage space (RAID 0)" of our tutorial on storage spaces on Windows.

As you can see, when you create a "Simple (no resiliency)" storage type with 2 x 500GB hard drives, your storage capacity is around 1TB (998GB in this case).

In file explorer, your storage "RAID 0 storage" with the same capacity as before (the total size of the physical disks used).
In our case, this storage space therefore has a capacity of 997 TB (approximately 1 TB).

In our "RAID 0 storage" storage space, we added several files so that the usage percentages change in the storage space management.

Once you have stored data in this "Simple (no resiliency)" type storage, you will see that the usage percentage for your different physical disks has changed.
In addition, you can see that Windows is automatically distributing the data across them.
Which is normal since this type of storage acts as a software RAID 0:

• half of each data on the 1st disk.
• the other half of each data on the 2nd disk.

Warning : as a reminder, this also means that if one of the physical disks in this storage space fails, you will lose all data in this storage space.

2. Add a physical disk to expand your storage pool

If you start to run out of disk space on your "Simple (no resiliency)" storage space, you can easily expand it by adding an additional physical disk to your storage pool. To do this, to the right of your storage pool, click "Add drives".

In the "Select drives to add to the storage pool" step that appears:

• select the new physical disk to add
• check the "Optimize drive usage to spread existing data across all drives" box.
• click the "Add drives" button.

Note: using the "Optimize drive usage..." option is optional and only possible from Windows 10.

Please wait while the drive usage optimization starts automatically.
As you can see, the physical disk you just added is currently used at about 0%.

Note: if you did not check the box previously, you will just need to click on the "Optimize drive usage" link located on the right side of your storage pool.

While optimizing drive usage, you will see that the usage percentage of your new physical disk will increase.
Note: the usage percentage of the others will decrease proportionally as your data is distributed across your physical disks.

Once the drive usage optimization is complete, you will see that the usage percentage of your physical disks will be the same or similar.

If you go to file explorer, you will notice that your "RAID 0 storage" storage size has not changed, despite adding a physical disk to your storage pool.
This is because an additional change is required for this size to be updated.

3. Increase the size of a single storage space (RAID 0)

Now that you have added a physical disk to your storage pool, you need to change the size of your storage space to be able to use the new disk space available on your storage pool.
To do this, to the right of your "RAID 0 storage" storage space of type "Simple (no resiliency)", click on the "Edit" link.

By default, Windows will display the current size of your storage space in the "Storage space size (maximum)" field.

To know what size you can use on your storage pool, just refer to the value indicated as "Available pool capacity".
To be sure not to indicate too large a size, we advise you to indicate the value "Available pool capacity" with one hundredth less.
Which gives in our case, a storage space size of 1.42 TB for an available pool capacity of 1.43 TB.

Warning : also make sure that the size displayed as "Including resiliency" is less than the "Available pool capacity".
Indeed, as indicated below, it is possible to create a storage space whose size exceeds the capacity of your storage pool.
If you try to store too much data in the future, Windows will ask you to add a physical disk because of the missing disk space.

Your storage space size has been increased.