Rooftop Solar Installation Process: Step by Step

The big picture: from first call to first bill

Going solar is a sequence of steps involving you, the installer and your electricity distribution company, the DISCOM. Knowing the sequence helps you plan your time, avoid mistakes such as installing before approval, and spot delays early. This guide walks through each step as it usually happens for a home system in Uttar Pradesh.

The exact order and timing can vary by DISCOM, scheme and installer, so use this as a rough map. Ask your installer to confirm the stages for your own case in writing.

Step 1: Site survey

The process starts with a visit to your roof. The installer measures the usable area, looks for shade from trees, tanks and neighbouring buildings, checks the roof's strength and waterproofing, notes the direction and tilt, and inspects your electrical connection: meter location, main panel, wiring condition and sanctioned load. They will also ask for your last several electricity bills.

A quotation sent without a visit is a guess. Everything else builds on the survey, and it is your chance to meet the people who will do the work. Ask questions, and make sure someone who will supervise the installation is present.

Step 2: Design and written quotation

After the survey, the installer proposes a system size, an array layout, the equipment brands and a price. A good quotation is specific: it lists the capacity in kW, the number and wattage of panels, the inverter make and rating, the mounting structure, cables, earthing and protection devices, and what is included or excluded, such as net metering fees or civil work.

Compare it with at least one other quotation, line by line. Ask what happens if the DISCOM requires a change in design, who pays for it, and what the payment schedule is. Agree on a schedule tied to milestones such as delivery, installation and commissioning, instead of paying everything in advance.

Step 3: Registration and approvals

Before installation, the application is registered with the DISCOM and, if you are claiming a subsidy, on the national portal. The DISCOM checks that your connection can accept the proposed system and gives approval to proceed. This is called technical feasibility, and it is the step that should happen before any equipment is installed.

Keep your application number safe and ask the installer to tell you when approval arrives. If you are claiming subsidy under the residential scheme, installing before approval can put the subsidy at risk, so wait for the go-ahead.

Step 4: Installation day

A home system is usually installed in a few days, though larger or more complex jobs take longer. The team first fixes the mounting structure to the roof, with proper anchoring and waterproofing around the fixings. Then they fit the panels, connect them in strings, run DC cables to the inverter, connect the inverter to your main panel through protective devices, and set up the earthing and lightning or surge protection.

You need not supervise the technical work, but be available to give roof access, answer questions and sign the delivery and installation records. Take photographs before, during and after the work, especially of the structure, the wiring and the earthing, since they are useful evidence later.

Step 5: Inspection, net meter and commissioning

When installation is complete, the installer informs the DISCOM and requests an inspection. A DISCOM officer visits to check that the installation matches the approved design and is safe. If everything is in order, the DISCOM installs a net meter, or replaces your existing meter with a bi-directional one, and the system is formally commissioned.

Do not switch the system on before this approval. Operating a grid-connected system before inspection can breach the rules and may delay your subsidy. After commissioning you receive a report or certificate, which you keep safely and, if applicable, submit on the portal along with your bank details.

Step 6: After installation

Once the system is running, take a moment to learn how to read the inverter display or app, and note the generation on a few clear days as a baseline. Ask the installer for the service contact, the warranty documents, a copy of the single-line diagram and a maintenance schedule.

Over the next billing cycles, check that your bill shows imported and exported units as expected. If the numbers look wrong, contact your installer and DISCOM with the meter readings and the dates. Problems raised early are easier to resolve than ones raised after many months.

• Learn to read the inverter and record baseline generation.
• Store all documents safely in paper and digital form.
• Note the dates of inspection and meter installation.
• Clean the panels sensibly and arrange an annual inspection.

How long does the whole process take?

The physical installation is the shortest part. Approvals, inspection and meter installation depend on the DISCOM's workload and can take from a couple of weeks to a few months in busy periods. Subsidy credit follows after commissioning and verification. Because no one can predict these timelines exactly, ask your installer for ranges and update dates, and be wary of anyone who promises an exact day for everything.

To keep the project moving, prepare your documents early, answer any DISCOM or portal request quickly and stay in touch with your installer.

How to prepare your home before installation day

Clear the way to the roof, including the staircase and any locked doors, and make sure the roof is accessible and safe. Move planters, furniture and stored items that could be in the way, and tell neighbours if scaffolding or noise is expected. Decide where the inverter will be placed, because it should be in a shaded, ventilated spot close to the main panel and meter, protected from rain and children.

Ask the installer whether any roof repairs or waterproofing should be done first, since it is much easier to fix a leaking roof before panels are fixed on it. Keep your latest electricity bill and identity documents handy in case the DISCOM or the installer needs them on the day.

• Clear access to the roof and the inverter location.
• Fix any roof leaks or damaged waterproofing beforehand.
• Keep documents and your application number within reach.
• Plan a safe place for equipment to be stored on the day.

Quality checks to carry out at handover

Do a short walk-through with the installer before you accept the work and make the final payment. Look at the mounting structure and check that it is firmly fixed and that the roof around the fixings is sealed. Check that cables are neatly routed, protected from sun and sharp edges, and labelled where appropriate. Make sure the earthing and surge protection described in the quotation are actually installed.

Check the inverter display shows normal operation and learn what the lights and messages mean. Confirm that you have all the documents, serial numbers and warranty cards, and ask for the service number. Only then release the final payment, and keep photographs of the completed installation for your records.