How to choose a solar installer in New Zealand

Choosing a solar installer in New Zealand is less about finding the flashiest panel brand and more about clear design, clean electrical work, honest exclusions, and paperwork that still makes sense when you sell the house.

You are buying a small power station on your roof. The right partner explains size, generation, warranties, network steps, and what happens if something fails in year six — not only how the render looks in the brochure.

This guide is a homeowner checklist. Home Solar Installation NZ introduces local installation partners for quotes; you still decide, and you can seek a second opinion yourself.

What good looks like before anyone visits

A serious enquiry process asks about your roof, shade, power bill or annual usage, goals (bill cut, EV, backup), and whether a re-roof is planned. Vague forms that only ask for a phone number and then hard-sell a package are a weak start.

Expect a design that states system size in kilowatts, expected annual generation for your orientation, panel and inverter models, and a price with inclusions and exclusions. If the first document is only a monthly repayment, ask for the technical quote behind it.

Credentials and compliance

Solar work sits on electrical and roofing craft. Confirm who holds the electrical practising licence for the connection work, who supervises apprentices, and who signs the Electrical Safety Certificate. For switchboard concerns with a licensed electrician, see Tromar Electrical at https://tromarelectrical.co.nz/

• Clear company identity, contact path, and physical service area
• Named products with model numbers, not only brand logos
• Written warranties for panels, inverter, battery, and workmanship
• Who lodges distributed generation with your lines company
• Who books inspection and what documents you receive at handover

How to compare two or three quotes

Force the quotes onto the same basis. Same approximate kilowatts, same whether scaffolding is included, same assumption about switchboard work, same battery yes/no. Then compare generation estimates, warranties, and exclusions.

Red flags

Pressure to sign today, refusal to put exclusions in writing, generation claims with no roof photos or orientation logic, and “government rebate” language that does not match current NZ residential reality all deserve a pause.

Be careful with unusually low prices that omit meter work, inspection, or switchboard upgrades. Be careful with unusually high prices that bundle a large battery you did not ask for. Ask what happens to support if the company changes ownership.

Design quality questions

Ask how shade was assessed. Ask whether microinverters or optimisers are proposed and why. Ask what export limit the network may apply. Ask whether the inverter leaves a path to add a battery later if you skip storage now.

A good designer would rather right-size than max out the roof. Oversizing for export alone is a weak strategy when buy-back rates sit well below retail import prices.

During install and after

Agree site protection, working hours, and who is home for access. On completion you should receive product warranties, the Electrical Safety Certificate, shutdown procedure, and clarity on monitoring apps.

Watch generation for the first billing cycles. If output looks wrong against the estimate, contact the installer early with screenshots and weather context. Keep documents with your house records for insurance and sale.

Using an introduction service without giving up control

An introduction or quote service can save time finding a local partner, especially outside the biggest cities. You should still read the quote, ask the checklist questions above, and get a second quote if anything feels unclear.

Home Solar Installation NZ can introduce you to a local solar partner. The form is free and there is no obligation to proceed. You remain the decision-maker on design, price, and timing.

Questions to ask on the sales call

Keep a short list beside the phone so the conversation stays concrete.

• Who designs the system, and who installs it — same company or subcontractors?
• What insurance covers work on my roof and electrical work?
• How many similar jobs have you completed in my area this year?
• What is the process if generation is well below the estimate after six months?
• Who do I call in year four if the inverter faults under warranty?

Deposits, contracts, and variations

Understand deposit size, refund rules, and what triggers progress payments. Variations for switchboard work or unexpected roof repairs should be priced before work continues, not sprung as a surprise on install day.

Take time to read the contract. If a clause is unclear, ask for plain-language clarification in email so you have a record. Pressure to skip reading is itself a signal.

Aftercare and reputation signals

Look for clear aftercare: monitoring support, warranty claim pathways, and whether local technicians handle call-outs. A national brand with no local service story can still work, but you should know the response path.

Reviews help, yet verify them against the quote discipline above. A five-star page does not fix a vague scope. Prefer installers who welcome detailed questions over ones who dodge them.

A short decision framework

Pick the installer who explains your roof honestly, prices the same scope clearly, owns the network paperwork, and leaves you with documents a future buyer will understand. Panel brand rank is secondary to that package.

If you are still early in research, read the cost, worth-it, and timeline guides on this site, then request a quote with your postcode and a few roof photos. Real numbers beat another hour of generic browsing.

Local knowledge versus national sales desks

Local crews often know which lines companies are quick, which suburbs have tricky wind or salt exposure, and which scaffold companies can access narrow sections. National desks can bring purchasing power and polished paperwork. Either model can work; what matters is who turns up on your roof and who answers the warranty call.

Ask where the install team is based and how call-outs are handled if you are outside the main centres. A beautiful Auckland showroom does not service a Southland fault by itself.

If subcontractors do the roof while a sales company holds the contract, clarify who owns defects. Split responsibility is fine when it is written down; it is painful when everyone points elsewhere after a leak.

How to run a fair second opinion

A second quote is not an insult; it is how adults buy capital plant. Give both installers the same bill data and roof photos so you are not comparing different imaginary houses.

When quotes diverge wildly on generation, ask each to show orientation, shade assumptions, and weather data. When they diverge on price, map inclusions. Often the gap shrinks once scaffold and switchboard work are aligned.

If one installer refuses to put assumptions in writing, that refusal is information. Choose the partner who can explain the engineering without theatre.

Workmanship details worth walking

Stand under the eaves and look at cable entry, UV protection on outdoor runs, labelling at the switchboard, and whether penetrations look deliberate. Neatness correlates with care, even if it is not a lab test.

Ask how earthing and bonding are handled, and how emergency shutdown is labelled for fire services. These are not gotcha questions; they are how you learn whether the crew thinks like electricians or like brochure sellers.

Photo the finished plant room and roof before the crew leaves. Those photos help future service calls and house sales.

Document pack you should walk away with

Before final payment, gather panel and inverter serials, warranty certificates, the Electrical Safety Certificate, shutdown procedure, monitoring login, and the network approval references you were given. Store them with the house file.

If any item is missing, pause. Catching gaps while the crew and office still have your job open is far easier than reconstructing paperwork years later for a claim or a sale.

A professional installer expects this request. Treat resistance as a warning sign, not as you being difficult.

Trust signals that actually matter

Prefer installers who show their work: marked-up roof photos, named products, written exclusions, and a network timeline. Prefer those who invite a second quote rather than fear it. Prefer those who talk about inspection and certificates as normal, not as optional extras.

Fancy websites help discovery. They do not replace a disciplined quote. Use both: find candidates online, then judge them on paperwork quality.

Bottom line on choosing an installer

Choose the partner who designs for your roof and bill, writes exclusions clearly, owns the network paperwork, and hands over certificates without drama. Then keep a second quote in your back pocket until those boxes are ticked. Hardware brands matter; process discipline matters more.

Final check before you sign

Sleep on the quote overnight if you feel rushed. Confirm deposit terms, exclusions, and the install week in writing. If those three items are clean, you are ready to proceed with confidence.