TL;DR
Typical UK solar panel installation takes 4–8 weeks from survey to generating. Free roof survey (1–2 weeks to book), quote and system design, DNO notification (G98 auto-accept in 20 working days; G99 takes roughly 8 weeks), install day on site (1–2 days), commissioning, then your MCS certificate and SEG setup.
We’re MCS-certified, HIES-registered and NAPIT-approved. We handle the DNO paperwork and submit your SEG application on your behalf. You don’t need to chase anyone.
How long does solar installation take?
A typical UK solar panel installation takes 4–8 weeks from first survey to your system generating. The on-roof work itself is 1–2 days. Most of the timeline is paperwork: the DNO application (2–8 weeks depending on system size under the ENA G98/G99 rules) and MCS certification after commissioning.
Here’s the honest breakdown. From the moment you book a survey, we’re usually on your roof within 2–4 weeks. The survey itself takes 45–90 minutes. You get a written quote within 3–5 working days. Once you say yes, we submit the DNO application the same week.
Small systems at or under 3.68 kW inverter capacity go down the G98 route — the DNO must respond within 20 working days and most auto-accept. Larger systems (above 3.68 kW, including almost anything with a battery hybrid inverter) are G99, which runs 4–8 weeks. We book your install slot the moment the DNO approves. Lead time on install day itself is typically 2–3 weeks.
Install day is one or two days on site. Scaffold goes up the day before or first thing in the morning. Panels, inverter and battery are fitted. We commission on day two. Your monitoring app is live before we leave. MCS certificate follows within 10 working days; SEG first payment usually lands on your third monthly bill.
Step 1 — Free roof survey
The survey is the most important hour of the whole project. Get it wrong and you end up with an oversized array, a poorly sited inverter, or a consumer unit that can’t take the load. That’s why we do it in person, not over video.
What we check, in order:
- Roof pitch and orientation. South is ideal. East/west split roofs are fine and spread generation across the day. 30–40° pitch is the sweet spot. We laser-measure, we don’t eyeball it.
- Shading survey. We do a full-day shading assessment using our scope — trees, chimneys, neighbouring extensions, TV aerials. Even partial shading on one panel drops a whole string’s output without optimisers.
- Rafter condition. We poke our heads into the loft and check rafter spacing, timber condition, and any signs of damp or pest damage. Panels are light per m² but they stay on the roof for 25+ years. The structure has to be sound.
- Consumer unit and meter location. We check fuse-board capacity, existing RCD protection, and the route from the proposed inverter site to the consumer unit and the meter. If the consumer unit’s old (wire-fuse or pre-BS 7671 2018), you may need an upgrade. We’ll flag it upfront, not surprise you later.
- Your actual usage. Bring a recent electricity bill. We look at kWh per year and the shape of your usage across the day — that’s what sizes the battery. Our sizing guide walks through the maths.
You get a written survey report back within 3–5 working days. It includes roof area, proposed panel layout, array orientation, expected annual kWh, and any structural or electrical notes. If we don’t think solar makes sense for your property, we’ll say so — that’s happened about 6% of surveys in 2025. We’d rather lose the quote than sell you something that doesn’t work.
Step 2 — Quote and system design
A proper solar quote isn’t just a total at the bottom. It should name every piece of kit, its wattage, the expected output, the payback assumptions, and the terms you’re signing up to. Here’s what ours contain — and what to watch for in quotes from elsewhere.
Every Lunar Solar quote includes:
- Panel make, model and wattage (we quote 470W N-type AIKO, Longi, or JA Solar — named, not “premium”)
- Inverter make, model, and whether it’s hybrid or string-only
- Battery model and usable kWh (not just nameplate kWh — LFP cells are usually 90–95% depth-of-discharge)
- Array layout diagram showing exact panel positions on each roof face
- Expected annual generation in kWh, modelled from postcode irradiance data
- Payback years, 25-year profit, and a line-item for the one inverter swap at year 12–15
- Scaffolding, electrics, DNO application, MCS certification and VAT line-items, itemised
Red flags in other quotes:
- No named inverter model. If the quote says “hybrid inverter” without a make and part number, walk away. The inverter is half the system reliability.
- Deposits above 25% of total. Never pay a deposit larger than 25%. Reputable installers use staged payments: deposit, pre-install balance, final after commissioning. Anyone asking for 50% upfront is a risk.
- Today-only pricing. A real quote is valid for 30 days minimum. “Sign tonight for a discount” is a pressure tactic, not a pricing policy.
- No generation guarantee or MCS certificate promise in writing. The certificate is what switches on your SEG earnings. Get it in the contract.
Step 3 — DNO notification (G98 / G99)
Your DNO — the Distribution Network Operator — owns the local cables and substation. They decide whether your neighbourhood grid can handle another solar system pushing electrons back. We handle this entirely for you. You won’t speak to them.
Two routes, set by inverter capacity under Engineering Recommendation G98 and G99:
G98 — up to 3.68 kW inverter (per phase)
Auto-accept route. We notify the DNO within 28 days of commissioning. No advance permission needed, no waiting around. Applies to most small on-grid systems without a battery — roughly a 3 kWp string on a 3.68 kW inverter.
G99 — above 3.68 kW, and almost all battery hybrids
Approval-before-install route. We apply with full system specs and wait for written acceptance. Statutory DNO response time is 65 working days but most regions turn it around in 4–8 weeks. Occasionally the DNO asks for an export limit (e.g. cap at 3.68 kW) if your local substation is constrained — the inverter handles that automatically.
The full framework lives on the Energy Networks Association site. You don’t need to read it. We do.
Step 4 — Scaffolding and install day
Install day is when the real work happens. Most jobs wrap in 1–2 days on site. Bigger arrays, two-storey terraces with difficult scaffold access, or in-roof integrated kits can push to three days. We’ll tell you exactly what to expect the week before.
A typical install day
Scaffolders arrive 7:30–8:00am. Scaffold is up in about 45 minutes for a standard two-storey detached — longer for tricky access. Our install crew of two or three arrives around 9am. Roof hooks go in first, then the aluminium mounting rails, then the panels snap into the rails with clamps. By mid-afternoon on day one we’re typically roof-side-complete.
Day two is inside. Inverter mounted on the wall in the loft or garage. DC cables run from the roof to the inverter via the loft or an external conduit. Battery mounted and wired in. Solar isolator and new breaker installed at the consumer unit (this is the only time your power is off — usually 1–2 hours). Everything to Part P of the Building Regs and to BS 7671 18th Edition (plus Amendment 2) for the wiring.
What happens to your electricity during install
For roughly 1–2 hours on day two, mains power is off at the consumer unit while we wire the solar isolator in. Routers drop. Fridges and freezers are fine so long as the doors stay shut — we’ve never had a customer lose food. If you’ve got medical equipment or anything else that can’t drop, tell us on survey day and we’ll plan around it.
Access and parking
We need space for a scaffold truck (7.5 tonne) on day one and day after install for scaffold-down. A van for the install crew itself. If you’re on a residents’ parking street or a red route, let us know in advance — we sort permits where needed. We also operate under CDM 2015 regs, so there’s a written site plan for anything above basic works.
Step 5 — Commissioning and handover
Commissioning is the moment the system goes live. The inverter is configured, the battery is programmed, the monitoring app is paired, and a full set of electrical tests runs through. You watch the first kWh land on the app. Proper satisfying.
The handover pack we hand over on the day contains:
- Electrical installation certificate (EIC) to BS 7671
- Part P Building Regs notification number
- Panel, inverter and battery warranty documents
- Inverter commissioning sheet with settings, firmware version, and export limit (if applied)
- Monitoring app login, already logged in on your phone before we leave
- Site-specific user manual and shutdown procedure
- Our 10-year workmanship warranty certificate
Don’t accept a handover without the monitoring app working on your phone. That’s the one piece that’s a pain to sort out remotely later. If yours isn’t live by the time the van pulls away, push back.
Step 6 — MCS certificate and SEG setup
MCS (Microgeneration Certification Scheme) is the UK quality scheme for small-scale renewables. It’s also the paperwork that qualifies you for the Smart Export Guarantee, the 0% VAT relief, and your insurance-backed guarantee. No MCS, no SEG payments — simple as that.
We submit your MCS certificate within 10 working days of commissioning. You get a digital copy by email. We simultaneously submit your SEG application to your chosen export supplier — Octopus Outgoing, EDF Export, British Gas Export, whoever you’ve picked. You don’t need to do anything.
First SEG payment typically lands 8–12 weeks after install. Your supplier needs two full smart-meter readings from your SMETS2 meter before paying you — that’s usually the delay. Once it kicks in, most Octopus customers see export credits on their third monthly bill. More on rates and suppliers in our SEG guide.
Why MCS certification matters
MCS isn’t optional. It’s the UK’s minimum bar for a trustworthy solar install, and it’s what every serious installer ships as standard. Here’s what it buys you:
- Warranty protection. Panel and inverter manufacturers void warranties if the installer isn’t MCS-registered. No exceptions.
- SEG eligibility. Ofgem SEG rules require an MCS certificate for the installation. No cert, no export payments.
- 0% VAT eligibility. HMRC’s VAT Notice 708/6 requires professional installation by a qualified installer. MCS is the default evidence.
- Insurance. Home insurers are more likely to cover an MCS install without fuss. Non-MCS systems sometimes need a separate schedule or get declined.
- Resale value. Buyers ask for the MCS certificate. Solicitors ask for it. Without one, your solar is a liability, not an asset.
Who to avoid. Non-MCS “handyman” solar jobs, cheap imports fitted by unqualified electricians, and the “free solar” cold-call scams that were rampant in 2012–2018 and still surface today. If someone calls you out of the blue offering free panels, it’s a rent-a-roof deal. Walk away.
Our workmanship warranty and insurance-backed guarantee
We’re members of four different schemes, each of which does something different. Here’s what each one actually covers:
- MCS: Installer and product quality standard. Every install we do is certified under MCS 3005 (solar PV design and install).
- RECC: Renewable Energy Consumer Code. Consumer-facing trade body — sets the contract terms and complaints process we’re bound by.
- HIES: Home Insulation & Energy Systems Contractors Scheme. Provides the insurance-backed guarantee (IBG) — a third-party insurance policy that honours your warranty if we ever went out of business. It covers the full workmanship period, underwritten by a regulated insurer.
- NAPIT: Competent-person scheme for Part P of the Building Regs. Lets us self-certify electrical work without involving your council’s building control.
- TrustMark: Government-endorsed quality scheme. A second layer of consumer protection on top of MCS.
Our own workmanship warranty runs for 10 years on everything we’ve physically done — roof penetrations, fixings, wiring, and finishes. Panel and inverter warranties are separate (25 years on panels; 10–12 years on inverters; 10 years on LFP batteries). Read the full warranty breakdown above.
Recent installs near you
We install across the South of England plus Bristol and Yorkshire. Each area page has recent case studies, local planning notes, and example system sizes.
See our full case studies for before/after photos and real generation numbers from customers.
Frequently asked questions
Will scaffolding damage my garden or driveway?
No. Our scaffolders lay boards under upright feet so nothing presses directly into lawn or block paving. Narrow side-returns and paved driveways are fine. If we do need to cross a border or lift a shrub, we agree it with you before the truck turns up. Any minor lawn compression flattens out within a week or two.
What happens if it rains on install day?
Light rain is fine. We work through it. Heavy rain, high winds over 25 mph, or lightning — we stop, pack down, and rebook the panel-lift part to the next suitable day. Scaffolding stays up. You're not charged for the delay. UK winters mean we've all learned to build around the forecast.
Do you need to come inside my house during the install?
Yes, but not for long. We need access to your consumer unit (fuse box) to wire in the inverter isolator and to run the DC cable down from the loft. Expect us inside for maybe 2–3 hours across the two days. We wear shoe covers, dust-sheet the route, and tidy up before we leave.
Where does the inverter go?
Usually the loft, a garage, or an outbuilding — somewhere cool, dry and ventilated. It needs to be within cable-run distance of the consumer unit. Hybrid inverters that pair with a battery tend to live in the garage or utility room because the battery does too. We agree the location on survey day, not install day.
Do you remove old roof tiles?
For a standard on-roof install, no. We lift a small number of tiles, slide the stainless roof hooks under, and re-seat the tiles over the top. Tile damage rate on our books sits under 1%, and we carry replacement tiles in the van. For in-roof (integrated) systems we do remove the tiles in the panel footprint and replace with the integrated flashing kit.
How noisy is the install?
Scaffold assembly is the loudest part — roughly 45 minutes of clanging first thing in the morning. After that, the panel install itself is surprisingly quiet. A cordless drill, a bit of hammering for the roof hooks, and conversation between the crew. No generators, no angle grinders. Most customers say they'd forgotten we were on the roof by lunchtime.
Will my electricity be off during the install?
Briefly, yes. We turn the mains off at the consumer unit while we wire in the solar isolator — usually 1–2 hours on day two. We'll tell you the day before so you can plan around fridge/freezer contents. Routers and Wi-Fi drop during that window. Everything else carries on normally.
What about my pets?
Cats usually vanish to the back bedroom and we don't see them again until we leave. Dogs are fine in the garden if the scaffolding's out of reach, but some get stressed by the ladder noise — a walk somewhere else on install morning is often kindest. We'll ask you about pets on survey day and work around them.
Does a solar install void my roof warranty?
If your roof is under warranty from the original installer, check the terms first. Some warranties require any roof penetration to be done by an approved contractor. Our MCS 3005 work meets the roofing industry standard, and we provide a 2-year workmanship warranty on penetrations. For almost all UK domestic roofs over 10 years old, there's no original warranty left to void.
How long until I get my first SEG payment?
First SEG payment lands 8–12 weeks after install, give or take. We submit the MCS certificate and SEG application on your behalf within 10 working days of commissioning. Your import/export supplier then needs two full meter reads from your SMETS2 smart meter before they pay you. Most Octopus customers see their first export credit on the third monthly bill.
More on the numbers, the tech, and the rules
If you’re still working out the maths, start with our ROI and payback guide. For system sizing, try the sizing walkthrough. Want to know which panels we install and why, see our panel buyer’s guide. For grants, read up on UK solar grants. Living in a listed or conservation-area property? Start with solar on listed buildings.
