Downlight Layout

Downlight Wall Offset Calculator

Estimate a wall offset from mounting height, beam angle, and a wall-wash target fraction.

Lighting calculator Downlight Layout Updated August 26, 2026

Inputs

Results

Estimated wall offset -- m
Beam diameter at wall -- m
Positioning note --
Calculation details
Estimated wall offset
-- m
Beam diameter at wall
-- m
Positioning note
--
Important notes
  • Wall appearance depends on optics, surface reflectance, aiming, and photometric distribution.
  • Australian standards may inform the project boundary, but this estimate is not an automatic compliance check.

Formulas

  • \(\displaystyle R = H\tan(\theta/2)\)
  • \(\displaystyle O_w = Rf\)
  • The wall target fraction is an explicit planning assumption, not a universal wall-wash rule.

Estimate a wall offset from mounting height, beam angle, and a wall-wash target fraction.

Downlight Wall Offset Calculator is a planning aid. Keep the target source, product data, measurement method, and project assumptions with the result. Confirm compliance, installation, certification, and safety decisions with the responsible professional.