Obstruction & View
Sunlight access for windows and gardens
Annual Probable Sunlight Hours (APSH) and Winter Probable Sunlight Hours (WPSH) measure the amount of sun a window or garden receives compared to the total possible sunny hours. The BRE 209 guidelines state that a reduction of more than 20% (APSH) or 4 hours in winter signals a material impact.
DL-Light computes both APSH and WPSH and checks them against BRE 209 guidelines, producing the required compliance report for UK planning submissions. Often used alongside VSC and No Sky Line.
- APSH: annual sunlight hours vs total possible
- WPSH: winter sunlight hours (21 December period)
- BRE 209 threshold check per window
- Used for windows, gardens, and open spaces
- Planning submission report
