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Manufacturer-input calculator

Hearth Pad Size Calculator

Add the floor-protection dimensions from your appliance's current installation manual to its footprint. The tool calculates total pad width and depth; it does not choose the required protection for you.

Enter manual dimensions

All fields must use the same unit.

Appliance footprint
Required floor protection beyond the appliance

Copy these values from the listed appliance manual or written project requirement. No defaults are provided.

Calculated footprint

Enter the appliance and manual measurements to build the pad outline.

Size is not the same as protection performance

A pad can have the right footprint and still be unsuitable. The appliance instructions may specify ember protection, thermal resistance, listed materials, seams, floor construction, connector clearances, or other conditions. This calculator adds dimensions only.

Where to get the inputs

  1. Locate the exact make, model, serial number, and certification label.
  2. Use the current manufacturer installation manual for that exact model.
  3. Confirm whether the manual measures from the body, legs, loading door, or another reference point.
  4. If the unit is unidentified, uncertified, modified, or missing its manual, stop and seek qualified advice instead of guessing.

Related checks

Missing the manual or appliance label?

Do not substitute a generic number. Use the readiness checklist and discuss the unidentified system with an independent qualified provider.

Start triage

Last reviewed: July 23, 2026. This tool performs arithmetic only and does not determine code compliance or safe materials.