A living digital representation of your building's physical infrastructure, enabling you to understand, manage, and optimize every system under one roof.
A digital twin is a comprehensive digital replica of a physical object, system, or environment. It goes beyond static documentation by maintaining a dynamic, continuously accurate model that reflects the real-world state of what it represents. Where a blueprint shows what was designed and a photograph shows a moment in time, a digital twin captures what actually exists and how it all connects.
The concept originated in manufacturing, where engineers needed virtual models of complex machinery to simulate performance and predict failures. But the principle applies anywhere physical systems are too complex to hold in one person's head, too distributed to inspect all at once, or too critical to leave undocumented.
Buildings are exactly that kind of system.
Every building is a collection of interconnected infrastructure systems: electrical circuits, plumbing networks, HVAC ducts, security devices, networking cables, gas lines, and solar installations. These systems are designed by different trades, installed at different times, and maintained by different people. Yet they share walls, interact with each other, and collectively determine whether a building functions safely and efficiently.
Today, most of this knowledge exists as tribal knowledge, locked in the heads of the people who installed it. When those people move on, the knowledge disappears. When something breaks, diagnosing the problem means opening walls and tracing wires by hand. When a new contractor arrives, they start from scratch.
At HomeRunbook, we represent building infrastructure as a graph: components are nodes, and the physical connections between them are edges. This topology model is the digital twin. It captures not just what equipment exists, but how everything is connected, what depends on what, and where each connection runs.
Building infrastructure is inherently a network. A circuit breaker feeds multiple outlets. A water main branches into supply lines. An HVAC trunk splits into ducts serving different rooms. Traditional documents (lists, spreadsheets, photos) flatten this structure. A topology graph preserves it, making the relationships between components first-class information you can query, validate, and reason about.
A topology-based digital twin is not a 3D rendering or a BIM model. It is not concerned with visual appearance or architectural aesthetics. Instead, it focuses on functional connectivity: which breaker protects which outlet, which valve controls which fixture, which switch triggers which camera. This is the information that matters when something goes wrong, when you need to plan an upgrade, or when you want to understand your building's systems at a glance.
Our digital twin spans all the major infrastructure trades in a single unified representation:
Panels, breakers, circuits, outlets, switches, and fixtures with automatic load calculations.
Supply lines, drains, fixtures, valves, and water heaters with flow topology.
Air handlers, ductwork, vents, thermostats, and zones with distribution mapping.
Cameras, sensors, locks, panels, and alarm devices with zone coverage.
Switches, access points, cable runs, patch panels, and device connections.
Sprinklers, risers, alarm pulls, smoke detectors, and suppression zones with coverage mapping.
Speakers, displays, amplifiers, signal runs, and control systems with source routing.
Meters, regulators, valves, lines, and appliance connections with shutoff mapping.
Panels, inverters, batteries, monitoring, and grid interconnection topology.
Zones, valves, controllers, sprinkler heads, and drip lines with scheduling and coverage mapping.
Phone lines, PBX systems, VoIP endpoints, demarcs, and punchdown blocks with circuit mapping.
Because all eleven trades live in the same model, you can see interactions that are invisible when each trade is documented separately: which breaker powers the HVAC unit, which network cable runs alongside the plumbing, which security camera covers the electrical panel, which fire suppression zone protects the A/V equipment room, which solar inverter feeds back through the main electrical panel, which irrigation valve shares a trench with the gas line, and which telephone demarc connects to the network closet.
A complete building digital twin in HomeRunbook consists of several layers working together:
A digital twin gives you a permanent, transferable record of your building's infrastructure. When you sell the property, the knowledge goes with it. When you hire a contractor, you can show them exactly what they are working with. When something breaks at midnight, you can identify the relevant shutoff without guessing.
Arriving at a job site with a complete digital twin means no surprises behind the walls. You can plan work accurately, order the right materials, and understand how your changes affect other systems before you make them. The twin validates your work as you go, catching errors before they become callbacks.
Managing multiple buildings means managing hundreds of interconnected systems. A digital twin gives you a single place to understand every property in your portfolio, track maintenance across all trades, and coordinate work between different service providers who each see only their piece of the puzzle.
A digital twin produced during an inspection is more valuable than a written report. It shows relationships between components, highlights potential issues structurally rather than just as text in a list, and gives the buyer a living document they can maintain going forward.
The fundamental shift a digital twin represents is the move from documentation that decays to documentation that lives. A paper blueprint is out of date the moment someone changes a fixture. A spreadsheet of equipment tells you nothing about connections. A folder of photos requires someone who was there to interpret what they show.
A digital twin, by contrast, is a structured, queryable, validated model that evolves with the building. It answers questions that no static document can: "What is connected to this breaker?" "If I shut off this valve, what fixtures lose water?" "Which rooms are served by this air handler?" These are the questions people actually ask about buildings, and a topology-based digital twin answers them directly.
A digital twin is not just documentation. It is understanding. It transforms a building from a collection of hidden, aging systems into a transparent, manageable, and valuable asset. At HomeRunbook, we believe every building deserves one.
Start mapping your building's infrastructure today. No CAD experience required.