Backup For
Historic Preservation & Restoration Contractors

The per-building record a preservation contractor cannot afford to lose

A preservation or restoration project generates a specific record for each building, and that record is what lets anyone, years later, know what was actually there before the work changed it. The list below is what a working preservation project file should be able to produce, for one specific building, on demand.

• Existing-conditions surveys and assessment reports
• Measured drawings and as-found documentation
• Material and mortar analysis notes
• Paint and finish investigation records
• Dated photographic surveys of conditions before, during, and after work
• Historic structure reports
• Treatment and scope narratives
• Shop drawings for replicated millwork and ornament
• Sample and mock-up approvals
• Client and review-board correspondence
• Subcontractor and specialty-trade invoices
• Permits
• Payroll
• QuickBooks and accounting records

Every one of those items describes a condition that existed at a single moment on a single building. A dated photograph of a cornice before it was taken down for repair is not a picture that can be retaken; the cornice on the scaffold that week is gone once the work is finished. A mortar analysis note that recorded the sand-to-lime ratio in a wall before repointing is not something that can be re-derived once the joint has been raked out and refilled. The measured drawing that captured a floor plan as it existed before a partition wall came down is the only surviving record of that layout. If the file is lost, the building itself cannot be consulted to reproduce it, because the building has already moved on to its post-work condition.

Why a preservation record is different from new construction or design documentation

A preservation contractor's exposure does not look like a general contractor's or an architecture firm's, and this record should not be treated like either one.

A general construction business builds new work against a set of plans it controls from the start; if a drawing is lost, the building it describes is usually still standing and can, in principle, be re-measured or re-verified against itself. A preservation contractor's core record is different in kind: it documents fabric that the work itself is about to alter or remove. Our page on backup for contractors and construction businesses covers the general contracting side of a project, erecting new work against a plan, and it is a useful comparison specifically because that trade does not carry this same problem. A preservation contractor conserves and repairs fabric that a review process examines for what it already is, not new work being erected from a design.

A preservation record is also not the same thing as an architecture firm's design deliverables. Our page on backup for architecture firms covers drawings, models, and renderings authored to describe something the firm is proposing to build. A preservation contractor's existing-conditions survey, measured as-found drawing, and dated photographic record document something that already exists, before the contractor's own work changes it. One record describes a design intent; the other is field documentation of a physical condition at a specific moment. Losing an architect's rendering means redoing a design task. Losing a preservation contractor's pre-work condition photographs means the underlying condition can no longer be documented at all, because the wall has already been opened, the finish already stripped, or the timber already replaced.

Where backup gaps hide in a preservation contracting business

• Everything routed through one back-office PC. Many small preservation shops keep every existing-conditions survey, measured drawing, material analysis note, and photographic record on a single Windows machine. That machine becomes the single point of failure for the documentation of every building the shop has ever worked on, not just the current job.
• Field photographs that never make it off the site tablet or phone. Dated pre-work and in-progress photographs are often taken on a foreman's phone or a field tablet and synced or copied to the office machine later, sometimes weeks later. If the device is lost, damaged, or reset before that transfer happens, the photographic record for that phase of work is gone, and there is no way to walk back onto a finished job and retake it.
• Preservation, CAD, or conditions-survey software mistaken for a backup. Software used to organize measured drawings, conditions surveys, or photogrammetry models holds pieces of the record, but the software storing your data is not the same as an independent backup you control. Access to a vendor account, or a login change, can disrupt your ability to pull a specific building's file on your own timeline.
• Material and finish analysis notes kept apart from the rest of the project file, with no second copy. Mortar analysis results, paint-layer investigation notes, and sample logs are sometimes recorded separately from the main project folder, in a lab report, a spreadsheet, or a notebook that gets scanned once and never backed up again. If that single copy is lost, the specific composition data behind a repair decision cannot be re-derived after the repair is complete.
• Cloud sync mistaken for backup. Cloud sync mirrors the current state of a folder. If a measured drawing file is overwritten, a photo folder is deleted during cleanup, or ransomware encrypts the local files, sync propagates that change to the cloud copy, often within seconds. Backup keeps point-in-time versions so a file can be recovered as it existed before the change. Sync alone cannot do that.
• An external drive or a site trailer treated as the backup plan. A drive plugged into the office PC, or field notes kept in a job-site trailer, protects against some risks but not against theft, fire, or a ransomware event that reaches every connected drive at once. It is not an off-site, point-in-time backup.
• QuickBooks and job-cost accounting stored on one machine with no second copy. Payroll, subcontractor and specialty-trade invoices, and job-cost accounting often live in a single company file on the office PC. Intuit's own documentation notes that keeping a backup copy only on the same machine as the original is not adequate protection against hardware failure.
• No tested restore process. A backup that runs without errors tells you that files were transferred, not that a specific building's existing-conditions survey or dated photographic record can actually be opened and read back. The gap surfaces only at the moment that specific file is needed.
• Backup media stored in the same building the shop operates from. A drive next to the office computer offers no protection when the event affecting the office, a fire, a burst pipe, a break-in, also reaches the backup copy. CISA guidance calls for at least one backup copy stored off-site, physically separate from the primary data, which for a single-location shop means a cloud destination outside the building.

Common failure scenarios for preservation and restoration contractors

These are the moments a backup gap turns from a theoretical risk into a real one. Each has a different trigger, but the outcome is the same when no independent, off-site backup exists.

Understanding the 3-2-1 backup rule for preservation contractors

The 3-2-1 rule is a framework promoted by CISA and used widely in small-business backup guidance. Applied to a preservation shop's project files, here is what it means in practice.

A backup standard for historic preservation and restoration contractors

The checklist below reflects CISA small-business backup principles and FTC small-business cybersecurity guidance, applied to the way a preservation shop actually stores its files. This is a starting framework for backup decisions. It is not preservation, conservation, treatment, tax-credit, grant, regulatory, or licensing advice, and it is not hazardous-material or job-site safety guidance.

• Map every machine and device that touches a project file. List the office PC, any secondary workstation, and every field phone or tablet used to capture conditions. For each one, identify what surveys, drawings, analysis notes, and photographs live there. That list is your backup scope.
• Confirm where your preservation, CAD, or survey software actually stores its data. Preservation and conditions-survey software, CAD applications, and photogrammetry tools keep records in a specific local folder, a device-synced app, or a vendor-hosted account. Find where that is and confirm it is included in your backup scope. Do not assume a software vendor's storage is a backup copy you can restore from independently on your own schedule.
• Back up field devices, not just the office. Any phone or tablet used to capture dated pre-work, in-progress, or post-work photographs should be part of your backup scope. A photograph of a condition that no longer exists cannot be retaken once the work is finished.
• Treat material and finish analysis notes as their own dedicated record. Whether mortar analysis results, paint-layer investigation notes, or sample logs live in a lab report, a spreadsheet, or a scanned notebook, treat that record as a specific item in your backup scope rather than assuming it is covered by a general folder backup.
• Keep a version history long enough to reach back before an incident. CISA guidance notes that ransomware and accidental deletions are often not discovered for days or weeks. A short retention window may not let you recover a clean version of an affected file from before the incident.
• Encrypt backup data in transit and at rest. Project files can include client correspondence and site-specific detail. Backup data should be encrypted before it leaves your environment and while it sits in storage.
• Monitor backup jobs and get alerted on failure. A backup that fails silently leaves current projects uncovered with no warning. Alerts on failed or missed jobs are a baseline requirement, not an extra.
• Test restores on a schedule. Pick a sample existing-conditions survey, a measured drawing, a dated photograph set, and a QuickBooks backup from a different date, and confirm you can retrieve and open each one. A quarterly spot-restore surfaces scope gaps before a real recovery is on the line.
• Write down who handles recovery and how. Someone in the shop should be able to answer, without searching, what is backed up, where it goes, and how a restore is started. A short note stored somewhere other than the machine being backed up turns a chaotic recovery into a manageable one.

If your projects also involve general contracting work on non-historic structures, see backup for contractors and construction businesses, which covers new-build project files rather than the pre-work conditions documentation this page focuses on. If your team also produces architectural design deliverables, see backup for architecture firms. If your projects involve structural or MEP coordination, see backup for engineering firms. For a broader self-assessment of your current backup posture, see the small-business backup checklist.

Preservation software and QuickBooks: what backup actually covers

Cloud sync is not a backup: what preservation contractors need to know

Many small preservation shops run OneDrive, Dropbox, or a similar sync service on their office machine and assume it protects their project files. The distinction matters most in the moments a real recovery is needed.

Cloud sync mirrors the current state of a file. When a measured drawing is overwritten, a photo folder is deleted, or ransomware encrypts a set of project files, that change replicates to the cloud copy, usually within seconds. At that point both the local copy and the synced copy reflect the damage, and the sync service has preserved nothing useful for recovery.

Backup keeps point-in-time copies with version history, so a project file can be restored as it existed at a specific date and time before the deletion, the overwrite, or the ransomware event. Microsoft's own OneDrive documentation describes version history and Personal Vault features, but these are limited by plan and duration and are not designed as a replacement for an independent backup with a defined retention window and active monitoring.

Ransomware and the preservation contracting business

The FTC and CISA both publish guidance noting that small businesses are targets of ransomware campaigns, in part because they often run with less IT infrastructure than larger organizations while still holding client records and financial information that create pressure to pay a ransom rather than lose the files.

For a preservation contractor, the factors that raise the stakes include years of existing-conditions documentation for multiple buildings concentrated on one Windows machine, dated photographic surveys that cannot be recreated once a project's physical conditions have changed, and typically no dedicated IT staff checking backup health on a regular basis.

CISA's #StopRansomware guidance identifies offline and encrypted backup copies as the primary technical recovery mechanism once ransomware has encrypted production files. A backup connected to the same network as the infected machine, or a sync folder replicating changes in real time, may itself be encrypted before the attack is even noticed. A backup that is not continuously mounted on the local network is the copy most likely to survive with usable project files intact. A tested backup does not eliminate downtime during a ransomware incident, but it is the difference between a difficult stretch of recovery and losing the only surviving record of what a building looked like before the work began, with no path back.

Two ways to get started

Whether you want to check your current situation yourself first or talk it through with someone who can give you a second set of eyes, there is a starting point that fits.