The best feature is undoubtedly the design of the houses, that keeps them cool without any artificial ventilation whatsoever. But you may already know about that from Getting it Right. And anyway, you could say it saved sweat and discomfort — not hard cash.
So, as best money saver, how about the windows — made a few miles away by Kasim in Kasese.
Building in Good Design
The windows we chose include an integral fire escape and have full height opening vents for good ventilation, making them ideal for the Ugandan climate.
Air conditioning was out of the question, however, so that doesn't count as money-saved.
The money-saver was in finding windows with integral fire escapes, providing high safety standards without the cost of separate fire exits.And in buildings used by such large numbers of children, good provision of fire escapes is vitally important.