More energy per panel
Every panel faces south and gives maximum generation, but the rows need spacing to avoid shade.
- Home
- Flat roofs
Commercial and residential buildings
Solar panels on a flat roof
On a flat roof the frame sets the tilt angle, and we space the rows so that they do not shade one another. Often the station can be installed without piercing the roofing at all.
Layout
South or east–west
Two main ways to arrange the rows. The choice depends on the roof area, your consumption pattern and wind load.
More panels on the roof
The rows stand in a “roof” pattern with almost no gaps. Generation is more even in the morning and evening, and the structure catches less wind.
No piercing, or rigid
Ballasted frames hold by their own weight and do not pierce the roofing. Anchoring is for roofs with a weight limit.
Roofing and mounting
How we mount on different flat roofs
We make the final decision after inspecting the roofing and assessing the load-bearing capacity of the slab.
| Roofing | How we fix it | Feature |
|---|---|---|
| PVC or TPO membrane | Ballasted frames on protective pads that do not damage the membrane. | no piercing |
| Torch-applied bitumen roofing | Ballast or anchors with joints sealed using a material compatible with the roofing. | your choice |
| Concrete slab | Frames anchored to the slab, or ballast blocks. | rigid fixing |
| Low-slope profiled sheet | Fixing to the sheet and purlins, with panels parallel to the roof or on low frames. | minimal weight |
Before installation
What we check on a flat roof
- Load-bearing capacity of the slabBallast adds weight, so it has to be taken into account together with the snow load.
- Waterproofing and drainageThe frames must not block the slopes towards the drainage outlets.
- Wind zonesThe wind is stronger near the edges and corners of the roof — there we use more ballast or a setback.
- Parapets and equipmentWe account for shade from parapets, ventilation and air-conditioning units in the layout.
- Maintenance walkwaysWe leave access to the panels and roofing for inspection and cleaning.
Compare layouts for your roof
The calculator shows how many panels fit with the “south” and “east–west” layouts.