Room sizing, heat gain, airflow and placement explained without relying on a single square-metre rule.
Conservatories often need more cooling than a normal room of the same floor area because the roof and glazing admit substantial solar heat. Orientation and shading can dominate the result.
A calculator can provide a screening estimate when its assumptions are visible, but it cannot see shading, construction, airflow or the proposed route. Treat the result as a starting range.
Cooling capacity may be shown in BTU per hour or kilowatts; 1 kW is approximately 3,412 BTU/h. Converting units does not complete the heat-load calculation.
Many bedrooms suit a small wall split, but square metres alone are not enough. Glazing, roof exposure, orientation, occupancy and the system's minimum output all affect the right choice.