A common call we get goes like this: “I’ve bought a 10kW inverter, now how many panels do I put on my 5 marla roof?” Sometimes the honest answer is: fewer than you’d like. So it’s worth measuring first.
- One modern panel is about 2.3 to 2.6 square metres.
- A 5kW system needs roughly 9 to 10 panels: plan for 30 to 35 square metres.
- A 10kW system needs about 60 to 70 square metres with walking space.
- Shade from tanks, walls and stairs often matters more than total area.
How big is one panel?
Most panels sold in Pakistan today are in the 550 to 600W range, and they’re roughly 2.2 to 2.3 metres long and about 1.1 metres wide. Call it about 2.5 square metres each. Older 330 to 450W panels are smaller but you need more of them for the same power.
Panels needed for common sizes
| System size | Panels (approx. 580W) | Panel area | Plan for (with gaps) |
|---|---|---|---|
| 3kW | 5 to 6 | 13 to 15 m² | 18 to 20 m² |
| 5kW | 9 to 10 | 23 to 25 m² | 30 to 35 m² |
| 10kW | 17 to 18 | 43 to 46 m² | 60 to 70 m² |
| 15kW | 26 | about 65 m² | 85 to 95 m² |
The extra space is for gaps between rows (so one row doesn’t shade the next in winter, when the sun is low), walking space for cleaning, and the structure itself.
What a 5 marla or 10 marla roof can hold
A 5 marla plot is about 125 square metres, but the usable roof is smaller once you take out the stair room, water tank and parapet edges. Many 5 marla roofs comfortably fit 5 to 8kW. A 10 marla roof can often take 10 to 15kW. Raised structures over the stair room and tank can add space.
Shade is the real limit
A water tank’s shadow in December is longer than you’d guess. Panels in a string are connected together, so shade on one can pull down several. Before deciding where panels go, look at the roof at 10 am and 3 pm in winter and note where shadows fall. Neighbour’s higher walls and trees count too.
Face south, tilt a little
In Pakistan, panels facing south with a tilt of around 20 to 30 degrees work well for the year. East-west layouts are fine when space is tight. They make a bit less in total but spread production more evenly across the day.
Next step
Once you know how many panels fit, match the inverter to that. There’s no point buying a 10kW inverter if your roof only takes 6kW of panels. Our load calculator helps you see the system size your appliances need, and we can check whether your roof can carry it.
Send us a photo of your roof
With a rough measurement and a picture, we can tell you how many kW fit realistically.