A typical home solar installation takes 1 to 2 days on site. The whole process, from first enquiry to a system that is generating and registered, usually takes a few weeks. It takes longer if your system is large enough to need approval from the local electricity network operator before fitting, where the target response time is 45 working days, or if you live in a listed building or need planning permission.
- 1 to 2 days on site for a typical home installation, scaffolding aside
- 28 days to notify the grid operator after installing a system up to 3.68kW on a normal supply (G98)
- 45 working days target for the grid operator to respond to a G99 application for larger systems, before fitting
- 10 working days maximum after commissioning for your MCS certificate
Most of the wait is not building work. It is surveys, design, legal notice periods and grid paperwork, and the good news is that almost all of it is handled by your installer. Here is each stage in order, what sets its length, and how to avoid delays.
The full timeline, stage by stage
| Stage | What happens | What sets the time |
|---|---|---|
| 1. Enquiry and quote | You share your address, usage and roof photos; the installer designs a system and prices it. | How quickly you can send photos and a recent bill or smart meter readings. |
| 2. Survey | A check of the roof, loft, fuse box and space for the inverter and battery, in person or remotely. | Booking. A remote survey from photos and satellite imagery is usually quicker. |
| 3. Contract and cooling-off | You sign the fixed written price. The law gives you 14 days to change your mind. | Work can start inside the 14 days only if you ask for that in writing. |
| 4. Grid application (larger systems) | For systems over 3.68kW on a single-phase supply, a G99 application to your network operator. | The network operator: a 45 working day target from a complete application. |
| 5. Planning (rarely) | Most homes are permitted development. Listed buildings and some conservation area cases need consent. | The council: usually up to 8 weeks for a decision. |
| 6. Scaffolding | Scaffold goes up, normally just before the fitting day. | A council licence if the scaffold stands on a pavement or road. |
| 7. Installation | Roof fixings, rails, panels, inverter, battery and wiring. | 1 to 2 days for a typical home. |
| 8. Commissioning and handover | Testing, switch-on, monitoring app set-up, handover pack. | Done on the final installation day. |
| 9. Registration | MCS certificate issued; G98 notification sent to the grid operator. | MCS: within 10 working days. G98: within 28 days. |
| 10. Export payments | You apply for a Smart Export Guarantee tariff with your chosen supplier. | Needs the MCS certificate and a smart meter that records exports. |
What happens on installation day
For a typical 10 to 14 panel system, the work runs like this:
- Before day one: scaffolding. The scaffold goes up around the working area, with a safe platform at the eaves. Scaffolding is included in our prices.
- Morning, day one: roof fixings. The team lifts tiles or slates, fixes roof hooks to the rafters, refits the covering over the hooks and bolts on the aluminium rails.
- Afternoon, day one: panels. Panels are lifted up, clamped to the rails and wired together. Cables are run into the loft through a sealed entry.
- Day two, or late day one on a simple job: inside work. The inverter and any battery are mounted, usually in the loft, garage or utility room. An electrician connects the system to your consumer unit, which needs a short power cut.
- Testing and handover. The system is tested and switched on. You are shown how to isolate it, how to read the inverter and how to use the monitoring app.
- After: scaffolding down once everything is signed off.
Our own employed install teams do this work, not subcontractors, so the people who fit the panels also wire and commission the system. You can read the whole process on our how it works page.
Why some installs take weeks and others take months
The size of the system: G98 or G99
This is the single biggest factor. The rules for connecting generation to the grid depend on how much the inverter can export:
- G98 (up to 16 amps per phase, about 3.68kW on a normal house supply). Install first, then notify the network operator within 28 days of commissioning. No wait.
- G99 (anything larger). Permission must be granted before installation. The network operator's target is 45 working days from a complete application, and the clock does not start until every document is in.
Systems whose inverters can export more than 3.68kW, which includes many with batteries, go down the G99 route. In some cases the export can be limited electronically to reduce the approval burden. We make every application for you and tell you at quote stage which route your system needs. See our guide to how many solar panels you need to judge what size suits you.
Your cooling-off period
Under the Consumer Contracts Regulations 2013, a contract agreed at your home, online or over the phone gives you 14 days to cancel. Work cannot start in that period unless you ask for it to, in writing. If you are in a hurry and certain, you can make that request; if not, the cooling-off period runs alongside any grid application anyway.
Planning, listed buildings and conservation areas
Most houses in England do not need planning permission for roof panels. If yours is listed, or a flat roof system in a conservation area needs prior approval, allow for the council's decision time, usually up to 8 weeks. Our planning permission guide explains when this applies.
The roof and the fuse box
Slipped tiles, rotten battens or an old consumer unit found at survey can add a visit. Fixing them before the install day is quicker than discovering them on it, which is why a proper survey matters.
Weather
High winds, heavy rain and ice stop roof work for safety. Winter installs are perfectly normal, but allow for the odd rescheduled day.
Watch the VAT deadline: residential solar panels and batteries are zero rated for VAT until 31 March 2027, then 5% from 1 April 2027. On a £9,295 solar and battery system, 5% would add £464.75.
Worked example: counting back from 31 March 2027
Say you want a 6.2kW solar and 10kWh battery system, which will need G99 approval, installed before the VAT rate changes. Count backwards:
- Latest sensible install date: aim for the week of 15 March 2027, leaving a fortnight's margin for weather and scheduling before 31 March.
- G99 approval needed by: Monday 15 March 2027.
- 45 working days before that: that is nine full working weeks, so the complete application needs to be with the network operator by Monday 11 January 2027.
- Before that: the survey, final design and signed contract, so you would want to have your quote agreed in December 2026.
For a smaller system under the G98 limit, none of the 45 working days applies, and a February 2027 order leaves comfortable time. The network operator may answer sooner than its target, but you cannot plan on it. If the VAT saving matters to you, do not leave a G99 system until the new year.
How to speed things up
- Send clear photos of every roof face, the loft, your fuse box and your electricity meter with your enquiry.
- Have your MPAN (the 13-digit supply number on your electricity bill) ready; it is needed for grid applications.
- Check you have a smart meter that records exports. If not, ask your supplier now, as you need one for export payments.
- If you live in a listed building or conservation area, say so at the start.
- Clear the loft hatch area and the space where the inverter and battery will go before installation day.
Ready to get the clock started? Request a free quote and a free survey, or look at our solar and battery packages and solar panel prices first. There is no deposit until the survey is done.
Sources
Grid connection rules: MCS, notifying DNOs and Energy Networks Association. MCS certificate timing: MCS installation standards. Cooling-off period: Consumer Contracts Regulations 2013, regulation 36. Scaffolding on the highway: Highways Act 1980, section 169. Planning: GPDO 2015, Schedule 2, Part 14 and Planning Portal. VAT: HMRC VAT Notice 708/6. Export payments: Octopus Energy, Smart Export Guarantee.
