A good site survey decides three things: how big the system can be, what it will cost to install, and whether anything will cause trouble later. Miss one detail (a staircase room's shadow, a three-phase meter, a 40 m cable run) and the quotation is wrong, the margin disappears, or the customer is unhappy.

Use this checklist on every visit. It takes 20–30 minutes once your team is used to it.

1. Customer and electricity details

Name, phone and WhatsApp number, and who will decide (owner, family member, society committee)
Last 6–12 months of electricity bills (photograph at least the latest one)
Consumer number and DISCOM name
Sanctioned load (kW) and supply type: single phase or three phase
Average monthly units and the highest month (summer)
Is there a DG set or an inverter/UPS already?

The sanctioned load matters: for net metering, many DISCOMs limit the solar size to the sanctioned load. If the customer needs more, a load enhancement application comes first.

2. Roof measurements

Roof type: RCC flat, metal sheet, tiled/sloped, or ground mount
Usable length × width (after leaving space at the edges)
Which way the roof faces (south is best in India; east/west lose roughly 10–12%)
Building height (G+ floors), for material lifting and cable length
Parapet wall height
Is the roof waterproofed? Any cracks or leakage? (Fix before installation, not after.)

3. Shade

Walk the roof at least once and note everything that casts a shadow:

Water tanks, staircase and lift rooms, solar water heaters
Neighbouring buildings and trees (ask whether a building is coming up next door)
Mobile towers, hoardings, cables

Write down when the shade falls (morning or evening). Morning and evening shade costs much less generation than shade between 10 am and 3 pm.

4. Structure

Standard low structure, or elevated structure (7–10 ft) so the roof can still be used
Sheet roofs: purlin spacing and condition, clamp type
Wind exposure (coastal areas, high floors)

5. Electrical

Location of the energy meter and the distribution board (DB)
Where the inverter will go: shaded, ventilated, within reach for the customer
Cable run from the roof to the inverter and from the inverter to the DB, in metres
Space for earthing pits (usually three) and the lightning arrester
Condition of the existing wiring and earthing

6. Practical things

Water on the roof for panel cleaning
Access for material: staircase width, lift, crane needed?
Who keeps the roof key; society permission needed?

7. Photos to take every time

Full roof (two corners)
Shading objects
Electricity meter
Distribution board
Inverter spot
Electricity bill
A quick line diagram or sketch with dimensions

8. Feasibility

Finish the visit with a clear call: Feasible, Feasible with changes (e.g. elevated structure, load enhancement) or Not feasible, and the recommended size in kW.

Do it on the phone, not on paper

In Nithyam, the solar site survey already has every field above, a photo checklist that shows what is still missing, and a feasibility status. The office sees the survey the moment it is saved, and the quotation can be filled from the system size in one tap.

Rooftop solar site survey checklist for Indian installers