Regulations
Daylight requirements differ from country to country, and often between assessment schemes within the same country. This section has one page per standard LUX supports or plans to support. Every page follows the same structure:
- Legal status — what kind of document it is and whether it is mandatory
- Requirement — metric, threshold, which spaces are assessed
- Calculation setup — reference plane height, grid spacing, wall offset, sky model, reflectances
- How LUX handles it
- Sources
Most of these standards use one of two metrics — the static daylight factor (DF) or the climate-based daylight autonomy (DA). Those two pages explain what each one is and the colour scale LUX uses for it.
Values marked ?? are not yet confirmed and will be filled in as we verify them against the official documents.
Standards covered
Daylight provision
The four rows below are actual national regulations — each one mandatory, issued by a national authority, and directly enforceable. (EN 17037 itself is not among them: it's a reference standard, not law, until a national code adopts it — see the note after the next table, and its own entry under Other requirements.)
Status reflects the current LUX Live release (v0.3.0). "Supported" means LUX Live reports compliance against that standard today; everything else is on the roadmap. LUX Certify computes daylight generically (full Radiance simulation) and isn't tied to a specific standard's compliance report yet, so it isn't broken out per row below.
| Standard | Country / scheme | Metric | Threshold | Status |
|---|---|---|---|---|
| BFS 2024:8 | Sweden (building code) | Daylight factor | DF ≥ 1.0 % over > 50 % of habitable-room area | ✅ Supported |
| AFS 2023:12 | Sweden (workplace regulation) | Daylight factor or daylight autonomy (via allmänna råd → EN 17037; no number in the binding rule) | Not specified; in practice either EN 17037's climate-based 300 lx/50 % method or the BFS 2024:8 DF ≥ 1.0 % criterion is applied, per room at fixed workstations | ✅ Supported (via the BFS 2024:8 proxy) |
| TEK17 §13-7 | Norway (building code) | Average daylight factor | Average DF ≥ 2.0 % per room | ✅ Supported |
| BR18 | Denmark (building code) | Glazing area (primary) or dynamic illuminance or other methods incl. DF | Glass ≥ 10 % of floor area, or 300 lx over ≥ 50 % of the area for ≥ 50 % of daylight hours | 🔜 Planned |
Calculation setup at a glance
| Standard | Reference plane | Grid spacing | Wall offset | Sky model |
|---|---|---|---|---|
| BFS 2024:8 | 0.8 m (convention) | 0.2–0.3 m (practice) | none | CIE overcast |
| AFS 2023:12 | 0.8 m (shared with BFS 2024:8) | 0.2–0.3 m (practice) | none | CIE overcast |
| TEK17 §13-7 | 0.85 m | EN 17037 formula | 0.5 m | CIE overcast |
| BR18 | 0.5 m | 0.2–0.3 m (practice) | 0.5 m | Climate-based (Route B); CIE overcast if using a DF-based "other method" |
| EN 17037:2018 | 0.85 m | p = 0.5 · 5log₁₀(d) m | 0.5 m | CIE overcast / climate-based |
EN 17037:2018 is the common reference behind most of the national codes here for daylight provision. Norway and Denmark point to it directly for that calculation method; Sweden's BFS 2024:8 is issued as SS-EN 17037 with a national threshold, and AFS 2023:12's allmänna råd cite it by name as an example assessment method. Where a national code is silent on a daylight-provision calculation detail, the EN 17037 value is normally used — this does not extend to the other, non-daylight requirements (view out, sunlight, glare), which each standard sets independently.
Other requirements
Not national daylight-provision rules. This covers three things: EN 17037 itself in full — including its own daylight-provision criterion (§4.1), since it is a reference standard rather than law and doesn't belong in the mandatory table above — plus its other three criteria; BR18's separate view-out requirement (§378, a Danish functional requirement, not based on EN 17037's own view-out criterion); and Miljöbyggnad's solar heat load indicator.
| Standard | Country / scheme | Requirement | Threshold | Status |
|---|---|---|---|---|
| EN 17037:2018 §4.1 | Europe (reference standard) | Daylight provision | Location-dependent; e.g. 300 lx over ≥ 50 % of the area for ≥ 50 % of daylight hours (Medium level) | 🔜 Planned |
| BR18 §378 | Denmark (building code) | View out | Required separately from the daylight-provision route | 🔜 Planned |
| EN 17037:2018 §4.2 | Europe (reference standard) | View out | Sight angle, outside distance, view layers — e.g. ≥ 28° / ≥ 20 m / two layers for the Medium level | 🔜 Planned |
| EN 17037:2018 §4.3 | Europe (reference standard) | Exposure to sunlight | Minimum sunlight hours on a reference day (1 Feb – 21 Mar) — e.g. 3.0 h for the Medium level | 🔜 Planned |
| EN 17037:2018 §4.4 | Europe (reference standard) | Protection from glare | Daylight Glare Probability (DGP) not exceeded for ≥ 95 % of occupied hours — e.g. DGP ≤ 0.40 for the Medium level | 🔜 Planned |
| Miljöbyggnad | Sweden (voluntary label) | Solar heat load (solvärmelast) — an overheating-risk measure, not a daylight metric | W/m² by certification level | 🔜 Planned |