Start with the local property, not a generic BTU chart
Knysna’s lagoon, forest edge and strong holiday-home market create a distinctive installation setting. Homes may be occupied seasonally, sit on sloped sites or use timber detailing that changes how pipework and condensate routes should be planned.
Large glazed living areas can gain heat quickly, while shaded bedrooms may need much less capacity. One oversized unit is not a substitute for measuring how each space is actually used.