Defaults reflect this space type. Same engine as the main calculator.
| Cooling load | — |
A conservatory is glazing on five of six surfaces — including the roof, the worst one. Summer solar gain routinely pushes interiors 10–15°C above ambient; winter reverses it. Effective cooling loads run 50–80 BTU per sq ft, and the swing between cloud and sun is faster than any thermostat cycle.
Order of operations: roof blinds or external shading (the single biggest lever), ventilation for shoulder seasons, then an inverter mini-split sized for the shaded-peak load — sizing for unshaded full sun buys a unit that short-cycles 300 days a year. Many conservatory owners find a heat-pump-mode mini-split doubles as the winter solution.
A typical conservatory (~180 sq ft) needs about 14,732 BTU/hr — a 1.5 ton unit in moderate US conditions; hot climates run 15–25% higher.
Plan on roughly 14,732 BTU/hr for a typical ~180 sq ft conservatory in a moderate climate, with the space-specific factors described on this page already included. Hot climates (Zone 1–2) add 15–25%.
Glass roofs admit solar gain no wall ever would, and the load swings minute-to-minute with cloud cover. Shade the roof first, then size an inverter unit for the shaded peak — brute-force tonnage just short-cycles.
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