Listing Folders & Subfolders & Size Export to CSV

I need help trying to list Folders and Subfolders and get there size in KB or  MB or GB or TB or PT  

and finally I need to export it to a CSV .

$startfolder = "c:\Temp" $folders = get-childitem $startfolder | where{$_.PSiscontainer -eq "True"} foreach ($fol in $Folders){ $colItems = (Get-ChildItem $fol.fullname -recurse | Measure-Object -property length -sum) If ( $colItems.sum -lt 1KB ) { $colItemsOutput = "$("{0:N2}" -f $colItems.sum) Bytes" } ElseIf ( $colItems.sum -lt 1MB ) { $colItemsOutput = "$("{0:N2}" -f ($colItems.sum / 1KB)) KB" } ElseIf ( $colItems.sum -lt 1GB ) { $colItemsOutput = "$("{0:N2}" -f ($colItems.sum / 1MB)) MB" } ElseIf ( $colItems.sum -lt 1TB ) { $colItemsOutput = "$("{0:N2}" -f ($colItems.sum / 1GB)) GB" } ElseIf ( $colItems.sum -lt 1PB ) { $colItemsOutput = "$("{0:N2}" -f ($colItems.sum / 1TB)) TB" } ElseIf ( $colItems.sum -ge 1PB ) { $colItemsOutput = "$("{0:N2}" -f ($colItems.sum / 1PB)) PB" }"$($fol.fullname) $colItemsOutput" | export-csv -notypeinformation -path c:\Temp\files.csv }