Create a benchmark report using the standard model

curl --request POST \
  --url https://api.n-3.co.uk/benchmark \
  --header 'Content-Type: application/json' \
  --header 'x-api-key: <api-key>' \
  --data '
{
  "total_gifa": 1500000,
  "individual_units": 12,
  "site_area": 15000,
  "location_index": 115,
  "start_date": "2024-11-01",
  "total_net_internal_area": 1000,
  "site_max_floors_above_ground": 2,
  "site_max_floors_below_ground": 1,
  "detached_garage_spaces": 0,
  "basement_parking_spaces": 0,
  "integral_garage_spaces": 0,
  "undercroft_parking_spaces": 0,
  "car_ports": 0,
  "surface_parking": 0,
  "primary_building_function": "residential",
  "primary_building_process": "new_build",
  "procurement_arrangements": "main_contractor_design_build",
  "demolition": 0,
  "contaminated_soil_removal": 0,
  "piling": 0,
  "basement_construction": 0,
  "structural_alterations": 0,
  "concrete_frame": 0,
  "lift_escalator": 0,
  "retaining_walls": 0,
  "diversion_of_services": 0,
  "drainage_pumping_station": 0,
  "electricity_sub_station": 0,
  "sprinkler_system": 0,
  "party_wall": 0,
  "balconies_terraces_winter_gardens": 0,
  "basement_car_parking": 0
}
'

[
  {
    "totals": 2571000,
    "external_works_variation": 100000,
    "total_including_external_works": 2571000,
    "total_adjusted_value": 2991359,
    "adjusted_cost_per_m2": 1994,
    "lower_limit": 1595,
    "upper_limit": 2592,
    "_meta": {
      "adjustment_percentage": 0.35,
      "external_works_percentage": 0.25,
      "strength": 75,
      "profiled_strength": 2.5,
      "location": {
        "county": "London",
        "index": 100
      }
    }
  }
]

POST

benchmark

curl --request POST \
  --url https://api.n-3.co.uk/benchmark \
  --header 'Content-Type: application/json' \
  --header 'x-api-key: <api-key>' \
  --data '
{
  "total_gifa": 1500000,
  "individual_units": 12,
  "site_area": 15000,
  "location_index": 115,
  "start_date": "2024-11-01",
  "total_net_internal_area": 1000,
  "site_max_floors_above_ground": 2,
  "site_max_floors_below_ground": 1,
  "detached_garage_spaces": 0,
  "basement_parking_spaces": 0,
  "integral_garage_spaces": 0,
  "undercroft_parking_spaces": 0,
  "car_ports": 0,
  "surface_parking": 0,
  "primary_building_function": "residential",
  "primary_building_process": "new_build",
  "procurement_arrangements": "main_contractor_design_build",
  "demolition": 0,
  "contaminated_soil_removal": 0,
  "piling": 0,
  "basement_construction": 0,
  "structural_alterations": 0,
  "concrete_frame": 0,
  "lift_escalator": 0,
  "retaining_walls": 0,
  "diversion_of_services": 0,
  "drainage_pumping_station": 0,
  "electricity_sub_station": 0,
  "sprinkler_system": 0,
  "party_wall": 0,
  "balconies_terraces_winter_gardens": 0,
  "basement_car_parking": 0
}
'

[
  {
    "totals": 2571000,
    "external_works_variation": 100000,
    "total_including_external_works": 2571000,
    "total_adjusted_value": 2991359,
    "adjusted_cost_per_m2": 1994,
    "lower_limit": 1595,
    "upper_limit": 2592,
    "_meta": {
      "adjustment_percentage": 0.35,
      "external_works_percentage": 0.25,
      "strength": 75,
      "profiled_strength": 2.5,
      "location": {
        "county": "London",
        "index": 100
      }
    }
  }
]

Overview

Generates a comprehensive benchmark report using N3’s standard cost prediction model. This endpoint creates cost forecasts based on similar projects, providing statistical analysis with confidence intervals.

Benchmark Types

Supports multiple benchmark approaches:

STANDARD - Single development benchmarking
COMPOSITE - Multi-development project analysis
PARTIAL - Individual development within composite projects

Model Capabilities

Cost Prediction Features

Statistical modeling using 50+ weighted factors
Confidence intervals (typically 75-85% confidence)
Real-time prediction updates
Quality assessment and validation

Input Requirements

Project characteristics (GIFA, location, features)
Development type and building specifications
Site constraints and procurement details
Budget data and timeline information

Quality Assessment

Benchmarks are evaluated through multiple quality checks: ✅ Data Completeness - Presence of out-turn cost data
✅ Statistical Validity - Average costs within confidence intervals
✅ Similarity Threshold - Combined scores ≤30 points for 3 projects
✅ Geographic Relevance - Location and time index alignment

Usage Examples

Standard Benchmark Request

{
  "projectId": "12345",
  "benchmarkType": "STANDARD",
  "includeComparisons": true,
  "generatePredictions": true
}

Composite Project Request

{
  "projectId": "12345", 
  "benchmarkType": "COMPOSITE",
  "developments": ["dev1", "dev2"],
  "hybridSupport": true
}

Response Structure

Returns comprehensive benchmark data including:

Cost predictions with confidence ranges
Similar project comparisons and scores
Quality indicators and health ratings
Statistical model metadata

Get Similar Projects - Find comparable projects
Create Snapshot - Save benchmark results
Get Project Report - Retrieve existing predictions

Authorizations

x-api-key

string

header

required

Body

application/json

total_gifa

number

Example:

1500000

individual_units

number

Example:

12

site_area

number

Example:

15000

location_index

number

Example:

115

start_date

string

Months from now until construction starts

Example:

"2024-11-01"

total_net_internal_area

number

Net internal area (NIA)

Example:

1000

site_max_floors_above_ground

number

Number of floors above ground

Example:

2

site_max_floors_below_ground

number

Number of floors below ground

Example:

1

detached_garage_spaces

number

Number of parking garages (detached)

Example:

0

basement_parking_spaces

number

Number of basement parking spaces

Example:

0

integral_garage_spaces

number

Number of parking garages (integral)

Example:

0

undercroft_parking_spaces

number

Number of undercroft parking spaces

Example:

0

car_ports

number

Number of carports

Example:

0

surface_parking

number

Number of surface parking spaces

Example:

0

primary_building_function

enum<string>

Primary building function

Available options:

residential,

residential_mixed_use,

student_accommodation

Example:

"residential"

primary_building_process

enum<string>

Primary building process

Available options:

new_build,

refurbishment_no_alterations,

extension,

refurbishment_with_alterations,

permitted_development,

air_rights

Example:

"new_build"

procurement_arrangements

enum<string>

Procurement arrangements

Available options:

main_contractor_design_build,

main_contractor_traditional,

self_build

Example:

"main_contractor_design_build"

demolition

number

Cost of demolition

Example:

0

contaminated_soil_removal

number

Cost of contaminated soil removal

Example:

0

piling

number

Cost of piling

Example:

0

basement_construction

number

Cost of basement construction

Example:

0

structural_alterations

number

Cost of structural alterations

Example:

0

concrete_frame

number

Cost of concrete frame

Example:

0

lift_escalator

number

Cost of lift escalator

Example:

0

retaining_walls

number

Cost of retaining walls

Example:

0

diversion_of_services

number

Cost of services diversion

Example:

0

drainage_pumping_station

number

Cost of drainage pumping station

Example:

0

electricity_sub_station

number

Cost of electricity sub-station

Example:

0

sprinkler_system

number

Cost of sprinkler system

Example:

0

party_wall

number

Cost of party wall

Example:

0

balconies_terraces_winter_gardens

number

Cost of balconies and terraces

Example:

0

basement_car_parking

number

Cost of basement car parking

Example:

0

Response

200 - application/json

totals

number

required

Total cost (sum)

Example:

2571000

external_works_variation

number

required

External works variation

Example:

100000

total_including_external_works

number

required

Total including external works

Example:

2571000

total_adjusted_value

number

required

Total adjusted value

Example:

2991359

adjusted_cost_per_m2

number

required

Adjusted cost per m2 (GIFA)

Example:

1994

lower_limit

number

required

Lower limit for adjusted cost per m2

Example:

1595

upper_limit

number

required

Upper limit for adjusted cost per m2

Example:

2592

_meta

object

required

Show child attributes

Save Document Studio Report Get a benchmark report using the standard model from project Id

⌘I

API Documentation

Analytics

Projects

Reports

Document Studio

Benchmarking

Community

Create a benchmark report using the standard model

Overview

Benchmark Types

Model Capabilities

Cost Prediction Features

Input Requirements

Quality Assessment

Usage Examples

Standard Benchmark Request

Composite Project Request

Response Structure

Authorizations

Body

Response

API Documentation

Analytics

Projects

Reports

Document Studio

Benchmarking

Community

​Overview

​Benchmark Types

​Model Capabilities

​Cost Prediction Features

​Input Requirements

​Quality Assessment

​Usage Examples

​Standard Benchmark Request

​Composite Project Request

​Response Structure

​Related Endpoints

Authorizations

Body

Response

Overview

Benchmark Types

Model Capabilities

Cost Prediction Features

Input Requirements

Quality Assessment

Usage Examples

Standard Benchmark Request

Composite Project Request

Response Structure

Related Endpoints