Most solar PV installs in Sussex take a single day. After 2–4 weeks of survey, design, paperwork and scheduling, the actual install is quick — once the scaffolding is up, the panels and electrical work usually happen within 8–10 hours.
This is what a typical solar install day looks like for a 4kW system on a Sussex semi-detached. Yours might be a bit different — bigger systems, batteries, complex roofs all add time — but the structure is the same.
Two days before: scaffolding
Most installs need scaffolding for safe access to the roof. A scaffold crew arrives 1–2 days before the install proper, usually first thing in the morning, and takes 2–3 hours to erect a simple side or rear scaffold.
Your installer should have given you the date and time. You don’t need to be in for the scaffold itself unless access is needed through the house.
Install day: 07:30 — team arrival
A typical install team for a 4kW system: two MCS-trained installers (often one lead and one apprentice or fitter) plus one qualified electrician. They arrive at 07:30, unload the panels, inverter, mounting rails, cabling and tools, and brief you on the day.
Useful to clear access to:
- Your consumer unit (fuse box)
- The location where the inverter will go (usually a garage, utility room, loft or cool corner)
- The route from the inverter to the consumer unit
- The roof side where the scaffold is
If you’ve got pets, this is the morning to keep them in one room. Same for kids. There’ll be ladders out, tools on the floor, brief power interruptions.
08:00–10:00 — roof preparation and mounting rails
The lead installer climbs up to the roof first, surveys the layout, and confirms the planned panel positions against the actual roof. Sometimes tiny adjustments are needed — a tile slightly out of position, a roof vent that needs working around.
Then the mounting hardware goes up: stainless or marine-grade hooks (depending on coastal exposure), connected to the roof rafters underneath the tiles. Aluminium rails run horizontally between the hooks. The rails are what the panels clamp onto.
By 10:00 you should see neat aluminium rails on the roof, ready for panels.
10:00–11:30 — panels up
Panels are heavy (typically 20–25 kg each for a residential 410W panel). They’re passed up to the roof installer one at a time, positioned on the rails, and clamped into place. Each panel takes 8–12 minutes from “on the ground” to “clamped in position and DC cable plugged in”.
Mid-string DC connectors join each panel to the next, forming a series chain. The end of the chain runs down through a roof penetration (usually a small lead-flashed hole at the eaves) into the loft or directly to the inverter.
By 11:30 on a typical 4kW install, the panels are physically up. Time for tea.
11:45–13:30 — inverter and DC cabling
While one installer finishes any roof tidying, the others work on the inverter side. The inverter is mounted on a wall in a cool, ventilated location — typically a garage, loft or utility room. DC cables from the panels are connected to the inverter input. DC isolator switches go on the inverter side and at the array if regulations require.
Battery installations (if you’re getting one) start here too. The battery is wall-mounted or floor-standing, connected to the inverter or its own battery management system, and to your consumer unit. Batteries add about 2–3 hours to the day.
13:30–15:00 — AC side and consumer unit
The electrician (often the lead installer) handles the AC side. AC output from the inverter cables back to the consumer unit. A new dedicated MCB (mini circuit breaker) goes in for the solar circuit. RCBO if required. AC isolator switch where regulations specify.
There’s usually a brief power cut here while the electrician works on the consumer unit — typically 10–30 minutes. If you’ve got medical equipment, sensitive electronics or a home office, mention this on survey day so we can schedule around it.
15:00–16:30 — commissioning and testing
Once the AC side is complete, the inverter is powered up for the first time. Initial commissioning checks include:
- Insulation resistance test on the DC side
- Earth bonding continuity check
- Inverter self-test (the inverter checks its own internal connections)
- Grid synchronisation — the inverter detects the grid frequency and voltage and matches them
- Generation start — sun permitting, the system begins generating
- Performance check — kW output measured against expected for the time of day and weather
By 16:00 (sun permitting) you should see the inverter display showing real-time kW generation.
16:30–17:30 — handover
The team walks you through:
- The inverter display — what it shows, what to look out for
- The app — most modern inverters (SolarEdge, GivEnergy, Tesla, Solis, etc.) have apps showing daily and lifetime generation. We help you set this up.
- The isolator switches — where they are, when you’d use them (basically never, except in an emergency)
- Battery operation (if relevant) — modes, settings, app control
- Paperwork — your MCS certificate (issued within 7 working days post-install), DNO notification, warranties, building regulations notification
- Smart Export Guarantee — how to apply, current best rates
Days after the install
Within 7 working days of install we register your system with MCS and you receive your MCS certificate by email. With that, you can apply for SEG (see our SEG guide) and start earning export income.
Your DNO (Distribution Network Operator — typically UK Power Networks in Sussex) is notified within 28 days as a formality. They don’t visit, they just record the new generation on their system.
Scaffolding usually comes down 1–3 days after the install.
Total time on site
Typical timings:
- 3kW install: one day, finish ~16:00
- 4kW install: one day, finish ~17:00
- 5kW install: one day, finish ~17:30, sometimes spilling into next morning
- 6kW+ install: two days
- Add a battery: +2–3 hours (usually fits in the same day for smaller systems)
- Add an EV charger: +2 hours
Bottom line
Solar installation is a short, focused process once the prep work is done. One day on site, a few minor power interruptions, a tea or two, and you’re generating. Most of the effort goes into the planning, design and paperwork before — by install day everything’s been mapped out.
If you’re scheduled in with us and want to know anything specific about your install day, just call or message. We’ll walk you through any questions.
