Daylight autonomy is the cheapest performance lever available to an architect, and it is routinely traded away in the first cost exercise.

What we modelled

We ran spatial daylight autonomy across six completed projects and compared measured lighting loads against the design-stage predictions.

What we found

Across the sample, payback on the additional glazing and shading sat under three years. In the two workplace projects it was under eighteen months, driven almost entirely by reduced daytime lighting load.

The uncomfortable conclusion: most value engineering exercises that remove glazing are destroying value, not protecting it.