Residential Solar Installation Guide: From Quote to Switch-On

A home solar project in the Philippines usually runs through ten stages: work out your electricity use, choose a system type, have your roof assessed, compare written quotes, check the installer’s credentials, sign a clear contract, secure LGU permits, apply for net metering with your distribution utility, install and commission the system, then monitor and maintain it. The paperwork has to happen in the right order, and a few documents only exist once others are done. A good installer manages most of this, but you should know what each step involves so you can spot gaps.

This guide walks through each stage, what to ask, and which documents to keep. It doesn’t replace advice from a licensed electrical engineer who has seen your property.

Step 1: Understand how much electricity you use, and when

Collect your last 12 months of bills and note the kWh (kilowatt-hours) used each month. One month can mislead you: use in the hot months of March to May is often higher than in the rainy season. Then think about when you use power. Solar produces during daylight, so a household that runs fans, a refrigerator, computers and an inverter aircon during the day can use more of its solar output directly than one that is empty until evening.

Useful tools:

• The electricity cost calculator and our guide to how to calculate your electricity bill help you understand where your kWh go.
• How many solar panels a Philippine home needs explains the sizing maths.
• The solar savings calculator gives a first estimate of what solar could offset.

A simple sizing check you can compare against installers’ proposals:

Approximate system size (kWp) ≈ daytime kWh you want to cover per day ÷ expected kWh per kWp per day

The “kWh per kWp per day” figure (specific yield) depends on your location, roof direction, tilt, shading and system losses. Ask each installer which figure they used and where it came from.

Step 2: Decide what you want the system to do

Your goal decides the system type:

• Lower daytime bills on a stable grid: an on-grid (grid-tied) system.
• Keep essentials running in brownouts: a hybrid system with a battery and a backup sub-panel.
• No reliable grid at all: an off-grid system.

Standard on-grid systems shut down during outages for safety reasons. Our comparison of on-grid, hybrid and off-grid solar explains the trade-offs. Make this decision before you collect quotes so all installers price the same thing.

Step 3: Site, roof and shade assessment

A proper site visit should cover:

• Roof direction and tilt. Which roof faces get the most sun, and how much usable area is free of vents, water tanks and edges.
• Shade. Trees, neighbouring buildings, water tanks and antennas. Even partial shade at certain hours can cut output. Ask how the installer assessed shade and whether the design uses optimisers or microinverters where shading is unavoidable.
• Roof condition and age. If the roof will need repair or replacement in the next few years, it is usually cheaper to do it before the panels go on.
• Roof structure. Whether the rafters or purlins and the roofing material can carry the panels and mounting safely, including wind uplift during typhoons (see Step 10).
• Electrical service. The condition of your service entrance, main panel and grounding, and where the inverter, isolators and any battery will go. Pick a shaded, ventilated spot above possible flood levels.
• Grid capacity. Your local transformer can limit how much solar you connect. Meralco, for example, publishes indicative hosting capacities for single-phase transformers. It lists about 7 kW for a 10 kVA or 15 kVA transformer and 10 kW for a 25 kVA transformer, with the final figure set by its own study. A careful installer raises this before finalising your system size.

Step 4: Get and compare at least three written quotes

Verbal estimates and one-line Facebook messages are hard to compare and hard to enforce. Ask for written, itemised quotes from at least three installers. Each quote should include:

To compare prices fairly, work out the cost per kWp for each quote:

Price per kWp (₱/kWp) = total quoted price (₱) ÷ system size (kWp)

A lower price per kWp is not automatically better. Check whether one quote leaves out permits, the net-metering application or a proper mounting system. For typical cost ranges, see solar panel prices and installation costs. Plug each quote’s price and estimated generation into the solar payback calculator to compare them on the same assumptions. Our compare solar quotes page has a printable checklist.

Step 5: Check the installer’s credentials

Who may sign plans and supervise the work

The New Electrical Engineering Law, Republic Act No. 7920, sets clear rules. Section 31 gives a Professional Electrical Engineer (PEE) the sole authority to seal electrical plans. Section 34 says no installation should be undertaken unless the plans and specifications have been prepared by or under the responsible charge of, and signed and sealed by, a PEE, and a construction permit has been secured first. The work must follow the Philippine Electrical Code and be done under the supervision of a PEE, a Registered Electrical Engineer (REE) or a Registered Master Electrician (RME), as the case may be.

In practice, ask the installer:

• Who is the PEE who will sign and seal your plans? Get their full name and PRC licence number.
• Who will supervise the work on site, and what is their licence?

You can check a professional licence on the PRC’s online verification portal (LERIS) at verification.prc.gov.ph.

Other checks

• DOE Solar PV Installer Registry. The DOE publishes an official registry of solar PV installers, updated as of 31 January 2026 at the time of writing. The registry itself says it is a reference for government entities and that the DOE does not endorse any listed installer. Being listed is a useful sign. Not being listed doesn’t by itself rule out an installer for a home project.
• Technician training. TESDA offers a Photovoltaic Systems Installation NC II qualification. You can ask whether the installation crew holds it.
• Track record. Ask for addresses or photos of similar residential jobs, ideally ones that have been through a typhoon season, and for references you can contact.
• Business registration and after-sales support. Confirm the company’s registered business name and address, and who you call when the inverter shows a fault.

Step 6: Sign a clear contract

The contract should repeat everything from the quote: equipment models, kWp, price, inclusions and exclusions, timeline, warranties and payment schedule. It should also say who is responsible for:

• LGU permits and the signed and sealed plans
• the net-metering application with your distribution utility
• what happens if the utility’s study limits your system size or requires upgrades
• roof leaks caused by the installation
• removing and reinstalling panels if the roof needs repair later

Payments tied to milestones (for example: deposit, equipment delivery, completed installation, successful commissioning) spread the risk between you and the installer.

Step 7: Permits from your LGU

You need an electrical permit from your city or municipality before installation, based on plans signed and sealed by a PEE. After installation, the LGU inspects the work and issues a Certificate of Final Electrical Inspection (CFEI), which your utility needs before it will energize a net-metered system.

Under Joint Memorandum Circular No. 001, s. 2026, issued by the DILG, DOE and DPWH, LGUs should process electrical permits for net-metering installations within 3 working days and issue CFEIs within 7 working days. The circular also sets a “no additional requirements” policy and deemed approval if the LGU fails to act in time.

Step 8: Apply for net metering with your distribution utility

If your system will export power, apply for net metering. Meralco warns that without a bi-directional meter, exported solar can be recorded as energy you imported. If you won’t export, Meralco offers a Zero Export arrangement instead. Check what your own utility offers.

At Meralco, the process runs through six stages: application, evaluation (a Distribution Impact Study), inspection of your service entrance, completion of documents and fees (including the CFEI and the ₱1,500 ERC Certificate of Compliance application fee), energization and commissioning, and filing with the ERC. Electric cooperatives and other utilities run their own versions. The DOE directed utilities and electric cooperatives in April 2026 to complete net-metering processing within 10 working days while the national energy emergency lasts.

Our net metering guide explains each step, how export credits are calculated, and the 2025–2026 rule changes.

Step 9: Installation, inspection and commissioning

A typical residential installation involves fixing roof attachments and rails, mounting the panels, running DC cables to the inverter, installing isolators, breakers and surge protection, connecting to your main panel, and setting up monitoring. Hybrid systems add the battery and a backup sub-panel.

After installation:

1. LGU inspection leads to the CFEI.
2. Utility testing and commissioning. Meralco’s commissioning tests include checking that the system disconnects within 2 seconds during an outage and reconnects only 10 minutes after power returns. Davao Light’s notice of the ERC’s September 2025 advisory says testing and commissioning are free and that any bi-directional meter fee is capped at ₱3,000.
3. Meter installation and start date. At Meralco, a special meter reading marks the start of net-metering service.

Documents to collect at handover

• As-built single-line diagram and layout, signed and sealed
• Datasheets and warranty certificates for panels, inverter, battery and mounting
• The installer’s workmanship warranty, in writing
• Electrical permit, CFEI, net-metering agreement and, later, the ERC Certificate of Compliance
• Monitoring app login and the installer’s support contact
• A written shutdown and restart procedure

Step 10: Monitoring, maintenance and typhoon season

Monitoring

Most inverters come with an app or web portal. Each month, compare actual generation against the estimate in your quote, allowing for weather. Output in the rainy-season months is usually lower than in the dry season. A sudden drop on a clear day can mean shading from a growing tree, a tripped breaker, a faulty panel or an inverter error. Report it to your installer.

Routine maintenance

• Cleaning. Dust, ash and bird droppings reduce output. Follow the panel maker’s cleaning instructions, and use a professional if the roof is high or steep. Never walk on panels.
• Visual checks. Look from the ground for loose panels, damaged cables or signs of water entry at roof penetrations.
• Inverter area. Keep it ventilated and free of clutter. Watch for error codes.
• Periodic professional inspection. Agree in the contract how often the installer will check connections, mounting bolts and protection devices.

Typhoon considerations

Typhoons are the main structural risk for rooftop solar here. Wind can lift panels and rails, especially near roof edges and corners.

• Design. Ask how the mounting was designed for wind loads at your location. The National Structural Code of the Philippines sets design wind requirements, and a licensed civil or structural engineer can check the roof and attachments against them.
• Equipment ratings. Panel datasheets and installation manuals state tested mechanical load ratings and the approved clamping zones. Check that the installer follows them.
• Fixing into structure. Attachments should be fixed into rafters or purlins, not just roof sheeting, and sealed against leaks.
• Before a typhoon. Follow your installer’s written advice. Don’t climb onto the roof in high winds.
• After a typhoon. Inspect from the ground. If panels, cables or the inverter are damaged, or anything got wet, switch off using the documented shutdown procedure and call the installer. Don’t touch damaged equipment.
• Insurance. Ask your home insurer whether the solar system is covered for typhoon and flood damage, and tell them about the installation.

The bottom line

A smooth installation comes down to good preparation and paperwork. Size the system from your actual bills and goals, have the roof and grid capacity checked, and compare at least three itemised written quotes. Confirm that a Professional Electrical Engineer will sign and seal the plans, and secure the LGU permits and CFEI. If you’ll export power, follow your utility’s net-metering steps in order. After switch-on, keep every document, track your output against the estimate, and plan for typhoon season. When you’re ready, use our compare solar quotes page to organise the quotes you collect.