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Challenge

Build an EnergyPlus Envelope Window U-Factor Retrofit Modeler

Parse EnergyPlus epJSON models to extract thermal envelope window specifications and synthesize window glazing retrofits. Calculate overall area-weighted U-factor reductions before simulation testing.

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Challenge brief

What you are building

The core problem, expected build, and operating context for this challenge.

Parse EnergyPlus epJSON models to extract thermal envelope window specifications and synthesize window glazing retrofits. Calculate overall area-weighted U-factor reductions before simulation testing.

Building energy consultant

Parse EnergyPlus epJSON document to isolate FenestrationSurface:Detailed and Construction objects.

Extract current thermal transmittance (U-factor) and surface area for each exterior glazing element.

Apply recommended high-performance triple-glazing retrofit parameters to target epJSON construction definitions.

Generate a calibrated epJSON delta patch alongside an area-weighted thermal transmittance comparison table.

Interactive parameter editor showing current window assemblies, target U-factor slider controls, epJSON diff view, and download link for updated models.

Download standard EnergyPlus epJSON example models from the public NREL EnergyPlus repository or generate mock epJSON fixtures. Starter examples below are synthetic. They are not downloaded records.

EnergyPlus Utilizes the EnergyPlus epJSON schema structure and construction definitions as documented in the EnergyPlus repository and input guides.

langgraph, pydantic, streamlit. LangGraph manages stateful cyclic steps across model parsing, thermal calculation, and epJSON diff generation with checkpointing. Hosted reasoning model capable of precise numerical computation and structured JSON mutation.

Submit runnable source, pinned dependencies, setup commands, a working interface, example outputs, and a recorded end-to-end demo. Include tests and an action log.

Parses FenestrationSurface:Detailed objects from epJSON and computes cumulative glazing surface area.

Calculates baseline versus retrofit area-weighted window U-factors.

Outputs valid, schema-compliant epJSON construction replacement blocks.

```json [ { "input": { "epjson_model": { "Window": { "Win_North": { "area_m2": 15, "current_u_factor": 3.2 }, "Win_South": { "area_m2": 25, "current_u_factor": 3.2 } } }, "target_glazing_u_factor": 1.1 }, "expected_output": { "total_glazing_area_m2": 40, "baseline_weighted_u_factor": 3.2, "retrofit_weighted_u_factor": 1.1, "thermal_improvement_percent": 65.62, "patch_applied": true } }, { "input": { "epjson_model": { "Window": {} }, "target_glazing_u_factor": 1.2 }, "expected_output": { "total_glazing_area_m2": 0, "baseline_weighted_u_factor": 0, "retrofit_weighted_u_factor": 0, "thermal_improvement_percent": 0, "patch_applied": false, "warning": "No fenestration surfaces found in model" } } ] ```

Thermal parameters and modified epJSON files serve as planning proposals and must be verified through certified simulation runs. Use mock external writes. Require human review before any real deployment.

Rules

Participation guide

Thermal parameters and modified epJSON files serve as planning proposals and must be verified through certified simulation runs. Use mock external writes and human review.

Delivery guide

How work is evaluated

Evaluation

Parses FenestrationSurface:Detailed objects from epJSON and computes cumulative glazing surface area. Calculates baseline versus retrofit area-weighted window U-factors. Outputs valid, schema-compliant epJSON construction replacement blocks.

Submission format

Runnable source, pinned dependencies, setup commands, working interface, example outputs, recorded demo, tests, and action logs.

Datasets

Challenge datasets

Public datasets, plus the private datasets you have access to.

Evaluation rubric

How submissions are scored

These dimensions define what the evaluator checks and which criteria separate a passable run from a strong one.

Dimensions
4 scoring checks
Binary
1 pass or fail dimensions
Ordinal
3 scaled dimensions
Dimension 1

Complete workflow

Parse EnergyPlus epJSON document to isolate FenestrationSurface:Detailed and Construction objects. Extract current thermal transmittance (U-factor) and surface area for each exterior glazing element. Apply recommended high-performance triple-glazing retrofit parameters to target epJSON construction definitions. Generate a calibrated epJSON delta patch alongside an area-weighted thermal transmittance comparison table.

Score scale
012
Score 0

Missing or incorrect.

Score 1

Partly complete, with documented gaps.

Score 2

Complete, with reproducible evidence.

Dimension 2

Correctness and evidence

Parses FenestrationSurface:Detailed objects from epJSON and computes cumulative glazing surface area. Calculates baseline versus retrofit area-weighted window U-factors. Outputs valid, schema-compliant epJSON construction replacement blocks.

Score scale
012
Score 0

Missing or incorrect.

Score 1

Partly complete, with documented gaps.

Score 2

Complete, with reproducible evidence.

Dimension 3

Review interface

Interactive parameter editor showing current window assemblies, target U-factor slider controls, epJSON diff view, and download link for updated models.

Score scale
012
Score 0

Missing or incorrect.

Score 1

Partly complete, with documented gaps.

Score 2

Complete, with reproducible evidence.

Dimension 4

Safe execution

Thermal parameters and modified epJSON files serve as planning proposals and must be verified through certified simulation runs.

Binary check

This dimension contributes its full weight only when the submission satisfies the requirement. Partial credit is not awarded.

Learning goals

What you should walk away with

  • Parse EnergyPlus epJSON document to isolate FenestrationSurface:Detailed and Construction objects.

  • Extract current thermal transmittance (U-factor) and surface area for each exterior glazing element.

  • Apply recommended high-performance triple-glazing retrofit parameters to target epJSON construction definitions.

  • Generate a calibrated epJSON delta patch alongside an area-weighted thermal transmittance comparison table.

Resources and assets

Reference links and supporting material

Dataset notes

Download standard EnergyPlus epJSON example models from the public NREL EnergyPlus repository or generate mock epJSON fixtures. Supplied starter examples are synthetic, not source extracts.

Challenge setup

Configuration summary for this challenge.

Challenge input

Input details are not configured.

LangGraph

Runtime for stateful agent workflows.

Evaluated output

No output checks are configured.

Evaluation checks
  • Parse EnergyPlus epJSON document to isolate FenestrationSurface:Detailed and Construction objects. Extract...
  • Parses FenestrationSurface:Detailed objects from epJSON and computes cumulative glazing surface area. Calcu...
  • Interactive parameter editor showing current window assemblies, target U-factor slider controls, epJSON dif...
Configured evaluation evidence
  • 2 public reference cases
Configured runtime
  • 2 configured tools

Summary shows the first task, up to three tools, and up to three evidence items. Open the technical recipe to view all configured items.

View technical recipe

Configured tools

Action Space
  • LangGraph · Optional
Orchestration
  • LangGraph · Optional

Evaluation contract

  • Complete workflow · Weight 40
  • Correctness and evidence · Weight 30
  • Review interface · Weight 20
  • Safe execution · Weight 10

Reference cases

  • 2 public reference cases

Workflow tasks

No workflow tasks are configured.

Recipe freeze marker

No recipe freeze time is recorded.

Frequently Asked Questions about Build an EnergyPlus Envelope Window U-Factor Retrofit Modeler