This question already has an answer here:
My office has multiple Windows 8 Machines and slow internet. Is there a place online I can download the 8.1 upgrade from home on my fast internet so I can do a network or usb install at the office? I don't want to have to download 3GB+ of updates on each and every machine through the Windows store over our slow internet connection.
The Windows 8 PC's in question are OEM Windows 8 Home, upgraded to Windows 8 Pro via the online Pro pack upgrade.