How can a small engineering or architecture practice work on large CAD and Revit files from home or on site without slow syncing or version clashes?

The short answer: reliable remote access to CAD files means keeping the heaviest working files in one controlled place. Usually that’s a well-set-up office server reached over a secure VPN, or a remote session to an office workstation. Then clear file-locking rules stop two people saving over each other.

This guide is for principals and practice managers at engineering and architecture practices in Meath, Cavan, Westmeath, Louth and Dublin. It covers sync limits, file locking, connection speed, site connections, backup and when outside help makes sense.

Why large CAD and Revit files struggle with cloud sync

Sync tools such as OneDrive work well for documents. However, large drawing and model files behave differently. Each save can mean a long upload. Worse, a half-synced file can open as an older version on someone else’s laptop.

Many design formats also don’t support several people editing at once in the way Word or Excel do. So when two people open the same file from synced folders, you can end up with conflict copies. That’s the main obstacle to remote access to CAD files through sync alone. Our post on SharePoint or a server for project files covers the storage limits and the wider choice. Here we focus on day-to-day working from home and on site.

First, check what your design software vendor recommends. Many vendors publish guidance on cloud-synced folders and shared models, and that guidance should shape your setup.

Remote access to CAD files through an office server and VPN

A common approach keeps live project files on an office server. Staff then connect from home over a VPN, so the server behaves like it does in the office. Alternatively, staff connect to a remote session on an office workstation. In that case, the heavy files never leave the building, and only the screen travels over the connection.

Either way, remote access to CAD files needs proper security. The Data Protection Commission’s data security guidance notes that remote access “creates a potential weakness in the system”. It also says to assess the need for it before granting access. Similarly, the National Cyber Security Centre’s guidance for SMEs recommends multi-factor authentication and VPN services for secure communications.

In practice, that means a supported firewall, multi-factor authentication on every remote login and practice-owned laptops. It also means removing access promptly when someone leaves.

Avoiding version clashes with file locking

Version clashes are usually a process problem as much as a technology one. For that reason, a few simple rules make remote access to CAD files safer:

• One working copy of each live drawing or model, in one agreed location.
• No personal copies on desktops or in Downloads folders.
• Use your software’s own locking or check-out features where they exist.
• Agree who owns each file during a busy stage of a project.
• Close files at the end of the day, so locks don’t block colleagues.

Working on a server rather than synced copies also helps here. When a file is already open, the next person usually gets a warning instead of a silent conflict copy.

Connection speed at the office and on site

Remote access to CAD files depends heavily on the office connection, and especially on upload speed. That’s because every file a home worker opens over a VPN travels up from the office line. By contrast, a remote session to an office workstation needs far less bandwidth, because only the screen image moves.

Inside the office, wired connections to workstations and the server usually beat Wi-Fi for large files. Our Wi-Fi and networking work covers cabling, switches and wireless together.

Remote access to CAD files from site with 4G or satellite

Sites often have weak or no fixed broadband. In those cases, practices typically use a 4G or 5G router, or a satellite broadband service. ComReg’s coverage map is a useful first check of mobile coverage at a site address. Still, test the connection on the day, because real speeds vary.

On a slower site link, a remote session usually works better than opening large files directly. Meanwhile, keep a small set of read-only drawings on the laptop for times when the link drops.

Backup and version history for design files

Version history helps when someone saves over a drawing by mistake. However, it isn’t a substitute for a separate backup. A Microsoft 365 backup covers email, OneDrive and SharePoint. But it doesn’t automatically cover files on an office server or workstation.

The NCSC guidance says to keep backups separate from the original data and to test them regularly. So if remote access to CAD files relies on a server, that server needs its own tested backup. Our post on IT support cost for engineers and architects explains how backup fits into a managed package.

When to bring in a managed IT provider for remote access to CAD files

Outside help usually makes sense when remote working is slow, unreliable or set up informally. It also makes sense when the server is ageing, when nobody owns security updates, or before a big hiring push.

Oliver Sweeney founded Sweeney Computer Services in 1985. Today, we support more than 50 businesses and more than 10 schools from Hurdlestown, Kells, Co. Meath. Our managed packages cover remote support, monitoring and patching, and security tools. In addition, device and server backup is available as part of a managed package, scoped in the proposal. We restore-test backups every two weeks, and you can request the records. Microsoft 365 licences are billed separately.

Above all, good remote access to CAD files should feel boring: files open, saves land and nobody overwrites anyone.

Read more about how we work with engineers and architects, and see our managed IT support packages.