The short answer
Carriers ask the agent for a property diagram, also called a plot plan, plot map, site diagram or sketch diagram, when they need to see how the buildings on a property sit in relation to each other and to their surroundings. The request comes most often for high-value or complex commercial properties, for specialty, excess and surplus (E&S) and inland marine risks, and when a COPE question is not answered by the imagery. PropDiagram makes the diagram from the street address in about a minute: every building numbered and measured, the distances you need, lot lines when available, and the hazards you mark, ready to attach to the submission.
Plot plan, plot map, site diagram, sketch diagram: what's the difference?
In insurance they mean the same thing: a drawing of the property seen from above that shows each building, its size and where it stands. Carriers, agents and inspectors use the names interchangeably, and an underwriter who asks for one will accept the others.
| Name | Where you'll hear it |
|---|---|
| Plot plan | Underwriting requests, builder's risk and construction projects, commercial submissions |
| Plot map | Farm and agribusiness risks, rural properties with several outbuildings |
| Site diagram | Loss control and inspection reports, industrial and manufacturing sites |
| Sketch diagram | Applications and supplemental questionnaires that ask for "a sketch of the premises" |
| Property diagram | A general term for any of the above |
A PropDiagram report is all of these: a scaled, numbered diagram of the buildings with their dimensions and footprint square footage, a building schedule and an aerial view. It is not a land survey; a plot plan prepared by a surveyor for a building permit is a different document.
When do carriers require a property diagram?
High-value or complex commercial properties
Carriers writing large commercial property schedules, industrial sites, manufacturing plants, or farm and agribusiness risks often require a plot plan to map out multiple buildings on a single lot, the distance between structures, fire walls and exposure points.
Specialty, E&S and inland marine lines
Excess and surplus lines carriers frequently demand site diagrams for unique occupancies, vacant buildings, builder's risk projects and high-hazard risks.
COPE questions the imagery doesn't answer
When satellite imagery does not clearly show clear spaces, hydrants or neighboring hazardous operations, the underwriter asks the agent for a physical or sketched plot diagram.
High-value and complex commercial properties
One policy can cover a plant, a warehouse, an office and a row of storage buildings on the same lot. The schedule lists them; the plot plan shows how they relate. The underwriter wants to see which buildings stand close enough for a fire to spread between them, where the separations and fire walls are, and what sits near the property line. On a farm or agribusiness risk the same question applies to barns, machine sheds, grain bins and the house.
Specialty, excess and surplus (E&S) and inland marine risks
Surplus lines carriers write the risks standard markets decline or can't classify, so they ask for more. A site diagram is a common requirement for:
- Unique occupancies that don't fit a standard class.
- Vacant buildings, where the carrier wants to see what else is on and around the lot.
- Builder's risk projects, where the structure is under construction and the plot plan shows what will stand where.
- High-hazard risks, where fuel storage, heat sources and the distance to other buildings drive the decision.
COPE: construction, occupancy, protection and exposure
Underwriters evaluate a property by its Construction, Occupancy, Protection and Exposure. Imagery answers some of that. When it doesn't clearly show the clear space between buildings, the nearest hydrant or a hazardous operation next door, the underwriter asks the agent for a plot diagram. This is what a PropDiagram report adds to each part:
| COPE | What the underwriter asks | What the diagram gives you |
|---|---|---|
| Construction | How big is each building, and how many floors? | Length, width and footprint square footage for every building; upper floors you enter. Construction type is not visible from above: put it in the building name, for example "Shop, steel frame". |
| Occupancy | What is each building used for? | Your own name for each numbered building on the schedule and the diagram |
| Protection | How far is the nearest hydrant? Can the fire department reach every building? | Adjacent streets on the diagram; the Measure tool keeps any distance you draw, for example from a building to the hydrant you see on the photo or know from the site |
| Exposure | What is next door, and how much clear space is there? | Distances between buildings; neighboring buildings within 250 to 1,000 ft; fuel tanks and outdoor wood boilers you place, each with its distance to the nearest building |
What should a plot plan for underwriting show?
| Item | In a PropDiagram report |
|---|---|
| Every building, numbered | Drawn and measured automatically; add or remove buildings with the tools provided |
| Use of each building | The name you type for each building |
| Dimensions and square footage | On every building and in the building schedule |
| Distance between buildings (clear space) | Measure tool; the line and distance print on the diagram |
| Neighboring exposures | Widen the range to 250, 500, 750 or 1,000 ft, or draw a rectangle around what matters |
| Fuel tanks and heat sources | Gas, diesel and propane tanks and outdoor wood boilers, with the distance to the nearest building |
| Hydrants and fire walls | Not detected automatically: measure to the hydrant and note fire walls in the building names |
| Lot lines and streets | Lot lines and lot size*; adjacent streets, labeled |
| Scale, north arrow and date | On every diagram; the report is dated |
* Lot sizes and boundaries when available
How do I answer an underwriter's request for a plot plan?
- Run the report. Enter the property address. The building footprints are drawn and measured automatically in about a minute.
- Check it against the site. Occasionally walls and dimensions may need to be tweaked for better accuracy: move a wall, add a building that is newer than the photo, remove one that isn't part of the risk.
- Show the exposures. Widen the range to take in neighboring buildings, and use Measure for the clear space between buildings and the distance to the hydrant.
- Mark the hazards. Place fuel tanks and outdoor wood boilers; each gets its distance to the nearest building.
- Name every building. Use names the underwriter will understand: occupancy, and construction or fire walls where they matter.
- Attach the PDF to the submission. The building schedule, aerial view and full-page diagram are in one file.
See how it works for every editing tool, or what's in a building footprint report.
Common questions
What is a plot plan for insurance?
A drawing of the property seen from above that shows each building, its size and where it stands in relation to the other buildings, the lot lines and the streets. Underwriters use it to judge fire spread, access and exposure. It is also called a plot map, site diagram, sketch diagram or property diagram.
Is a plot plan the same as a site diagram or a sketch diagram?
In insurance, yes. Carriers, agents and inspectors use plot plan, plot map, site diagram, sketch diagram and property diagram for the same thing. A plot plan prepared by a surveyor for a building permit is a different, surveyed document.
When do carriers require a property diagram?
Most often for high-value or complex commercial properties (large schedules, industrial sites, manufacturing plants, farm and agribusiness risks), for specialty, excess and surplus (E&S) and inland marine risks such as unique occupancies, vacant buildings, builder's risk projects and high-hazard risks, and when satellite imagery does not answer a COPE question.
Why does an underwriter ask for a diagram when there is satellite imagery?
Imagery does not always show the clear space between buildings, the nearest hydrant or a hazardous operation next door. A plot diagram from the agent answers those questions for the file.
What does COPE stand for?
Construction, Occupancy, Protection and Exposure: the four things an underwriter weighs when evaluating a property.
Does PropDiagram show fire hydrants and fire walls?
Not automatically. Use the Measure tool to draw and keep the distance from a building to the hydrant, and note fire walls or construction in the building names.
How do I pay for a plot plan from PropDiagram?
Pay per successful report or subscribe monthly with reports included; current rates are on the Pricing page. It takes about a minute from the address.
A PropDiagram report is a diagram and reference record. Measurements are approximate ground-footprint estimates from aerial-imagery-derived building outlines. A report is not an appraisal, survey, replacement cost estimate or insurance valuation; verify anything a decision depends on.