Grout & Adhesive Coverage Calculator implementation

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

t7-125

Effect

Computation or source lookup only

Input and validation requirements

The calculator can produce an undefined thinset result when coverage_per_bag is zero unless it rejects the input. Results are also non-unique without a supplied manufacturer lookup table, and an unlabelled area-unit convention changes the computed material substantially.

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": {
    "area_ft2": 100,
    "tile_length_in": 12,
    "tile_width_in": 12,
    "joint_width_in": 0.125,
    "grout_depth_in": 0.25,
    "thinset_notch": "1/4 x 1/4 in square notch",
    "thinset_bag_size_lb": 50
  },
  "expected_outputs": {
    "grout_weight_lb": 0.19485,
    "thinset_bags_exact": 1.11111,
    "thinset_bags_to_buy": 2
  },
  "reference_data": {
    "grout_density_lb_per_ft3": {
      "value": 110,
      "source_convention": "widely tabulated standard value; nominal cementitious-grout density, product-specific variation applies"
    },
    "thinset_coverage_ft2_per_50lb_bag": {
      "notch": "1/4 x 1/4 in square notch",
      "value": 90,
      "source_convention": "widely tabulated standard value; typical published thinset-coverage reference, manufacturer-specific variation applies"
    },
    "unit_conversions": {
      "in_per_ft": 12,
      "in2_per_ft2": 144,
      "in3_per_ft3": 1728,
      "source_convention": "widely tabulated standard exact unit conversions"
    }
  },
  "working": "Joint-cell dimensions: 12 + 0.125 = 12.125 in in each direction. Joint cross-sectional area fraction = (0.125 × 0.25) / (12.125 × 12.125) = 0.03125 / 147.015625. Grout volume = 100 × 144 × 0.03125 / 147.015625 ÷ 1728 = 0.00177136 ft3. Grout weight = 0.00177136 × 110 = 0.19485 lb. Thinset bags = 100 ft2 ÷ 90 ft2/bag = 1.11111 bags. Round upward: ceil(1.11111) = 2 bags."
}

Other records

Sources and evidence

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

• VERIFIED_LEDGER.json
• evidence-tranche7/tranche7-results.json