Observed arrival · 2026-09-03
Heat Loss Calculator
A room-by-room heating calculator that estimates building heat loss in watts, kilowatts, and BTU/hr.
Field notes
The calculator builds an estimate from room dimensions, exposed-wall count, envelope choices, glazing area, door type, air-change assumptions, and design temperatures. Its result separates fabric transmission from infiltration and thermal bridging, then shows room-level figures such as radiator output and approximate boiler contribution. Presets include U-values for several wall, window, roof, and floor constructions, while location options range from London and Edinburgh to New York, Chicago, Toronto, Berlin, Paris, and Sydney.
Observed signals
Read the marks
Editorial observations of this landing page, not a rating.
One card from the complete issue