Source: https://guthlabs.ai/docs/instruments/window-door-rough-opening-calculator/implementation/

instrument implementation / implementation-contract

# Window/Door Rough Opening Calculator implementation

A source-bound implementation contract for Window/Door Rough Opening Calculator; deployment and executable qualification remain separate.

Status: **VERIFIED_CLEAN**Lifecycle: **implementation-contract**

## Binding contract

This record describes what an executable surface must bind and validate. It does not claim that a public calculator, package, or production route is deployed.

**Record owner**: Guth Instruments

**Lifecycle**: verified-clean

**Evidence ID**: t5-153

**Effect**: Computation or source lookup only

## Input and validation requirements

Extreme but representable numeric inputs overflow to Infinity in JavaScript, zero dimensions can produce numerically valid but physically invalid openings, and an unlabeled clearance value is conventionally ambiguous and can change the result by 1 inch in each dimension.

## Required corrections

No binding erratum is attached to this unique-name record. Implementers must still preserve the declared units, domain, and failure behavior.

## Inspectable interface fixture

The sample below is evidence for interface and validation tests, not a production implementation.

````
{
  "inputs": {
    "unit_width_in": 36,
    "unit_height_in": 48,
    "clearance_per_side_in": 0.5
  },
  "expected_outputs": {
    "rough_opening_width_in": 37,
    "rough_opening_height_in": 49
  },
  "working": "Width: 36 + (2 × 0.5) = 36 + 1 = 37 in. Height: 48 + (2 × 0.5) = 48 + 1 = 49 in."
}
````

## Other records

[01**Overview**](<https://guthlabs.ai/docs/instruments/window-door-rough-opening-calculator/>)[02**Mechanism**](<https://guthlabs.ai/docs/instruments/window-door-rough-opening-calculator/mechanism/>)[04**Qualification**](<https://guthlabs.ai/docs/instruments/window-door-rough-opening-calculator/qualification/>)

## Sources and evidence

These pointers bind the page to evidence. They do not grant authority or collapse verification into deployment.

- `VERIFIED_LEDGER.json`

- `evidence-tranche5/tranche5-results.json`