Solar Substructure on Hall Roofs: Types, Calculation & Profitability
An industrial hall roof is an untapped resource. With the right substructure, every hall can generate electricity — and return the investment in 5-7 years.
An industrial hall roof is one of the largest untapped assets in any investor's portfolio. A solar substructure turns that dead cost into income — 350+ panels per hall, without changing the statics, without penetrating the roof.
Here's what you need to know about substructure types, structural calculations, and profitability.
3 types of solar substructure
Structural calculation — why it's critical
A solar substructure isn't just a panel carrier — it transfers wind and snow loads directly to the hall's steel structure. Every system requires structural calculation per Eurocode 1 and EN 1090.
| Load | Typical value | Standard |
|---|---|---|
| Panels (G) | 15-20 kg/m² | Manufacturer data |
| Wind (W) | 0.5-1.2 kN/m² | Eurocode 1 / location |
| Snow (S) | 0.4-1.6 kN/m² | Eurocode 1 / location |
| Seismic (E) | Zones 1-3 for HR | EN 1998 / national annex |
Yield and ROI — concrete numbers
For a 40×60 m hall (2,400 m² roof), usable panel area ~1,600 m², it's possible to install 350-400 panels at 400 Wp = 140-160 kWp total.
System comparison for different roof types
| Roof type | Recommended system | Panel tilt | Note |
|---|---|---|---|
| Flat roof (0-3°) | Ballast with triangular frame | 15-25° | No penetration, easy removal |
| Sloped trapezoidal sheet | Rail-fastened system | = roof slope | Minimal visual impact |
| Sandwich panel roof | Special clamps | = roof slope | No thermal bridges |
| Parking lot | Steel carport frame | 10-20° | Power + shade for cars |
Solar system integration with the hall — one-stop-shop advantages
RAKUŠIĆ designs and builds the complete package: steel hall + solar substructure + carport structure — all from one source, with the same structural engineers and one warranty document for the entire structure.