Installation Day Guide

What to Expect on Installation Day

A typical domestic solar installation takes one to two days. The main stages are:

1. Scaffolding erected — often done a day or two before the main installation.
2. Brackets and rails fixed to roof — tile hooks, rails, and mounting hardware installed.
3. Panels mounted — panels fitted to rails and wired up.
4. Inverter and battery installed — connected to your home's electrical system. Power may be off briefly.
5. System commissioned and tested — installer verifies everything is working and runs final checks.

Before Work Begins

1. Verify MCS/Flexi-Orb certification is current.— Don't assume it's valid — check it on the day at mcscertified.com. A certificate that was valid when you booked may have lapsed.
2. Confirm the equipment matches your quote and DNO approval. — Check panel brand/model, inverter, battery, and any other components against what was quoted and approved. Any substitutions should be agreed in writing before work starts.
3. Check all kit is new and in good condition. — Look for signs of wear, repackaging, or missing seals. There have been instances of installers using equipment removed from other installations.
4. If total inverter capacity will exceed 3.6 kW — ask to see the DNO G99 approval before they start. — Without G99 approval in place before installation begins, you risk issues with your export MPAN and export tariff application later.

During Installation — Roof-Mounted Panels

Scaffolding & Roof Structure

5. Scaffolding vs ladders — confirm it matches what was quoted.
6. Are the tile hooks correct for your specific roof type? If unsure, post a photo in the community before letting them proceed.
7. Are holes being pre-drilled for tile hook screws? (They should be.)
8. Are tiles sitting flat and flush after hooks are fitted?
9. Do rails look straight and parallel?
10. As panels go on — do they look level and aligned with each other?
11. If you have loft access — check inside the roof. Look for screws that have missed or cracked rafters, and check the roofing membrane hasn't been punctured.
12. Check for leaks — either during rain, or on the first rainy day after install.

Wiring & Cabling

13. Are panel cables neatly cable-tied — not left loose to rub and wear?
14. Is all electrical cabling tidy, and ideally run in conduit?
15. Is any external underground cabling buried and protected from damage?
16. Are warning labels in place on cables, the inverter, and the fuse board?
17. Solar/battery circuit on its own RCD in the fuse box? (It should be on a dedicated RCD, not shared with other circuits.)

Bird Proofing

18. Is bird proofing mesh attached using proper purpose-made clips? (Should be proper clips, not screws through panels or frames.)

Inverter Installation

19. Is the inverter mounted on heatproof material with sufficient air circulation clearance? Check the installation manual for minimum clearance distances. Overheating is a common cause of performance issues.
20. Are there any active inverter error codes from during the install? Ask the installer to clear the error log before commissioning so your system starts clean.

During Installation — Ground-Mounted Panels

21. Confirm whether planning permission is required for your ground mount.
22. Are panel rows spaced sufficiently to avoid inter-row shading?
23. Are all panels on each string at the same aspect, orientation, and pitch?
24. Are cable runs from panels buried and protected from damage?

During Installation — Battery Storage

25. Are heat/smoke detectors and a suitable fire extinguisher fitted near indoor batteries?
26. Are batteries in a rack or separated with proper stackable brackets? (Should be racked or bracketed, not stacked directly on top of each other.)
27. Is there sufficient clearance between batteries and adequate air circulation? Check the battery installation manual for minimum clearance requirements.
28. Will batteries be exposed to temperature extremes — loft heat in summer, garage cold in winter? Consider insulation for winter and ventilation or cooling for summer.
29. If EPS/UPS is being installed — does it have its own dedicated earth, signed off by a qualified electrician?
30. Has the installer set preferred battery charge/discharge times? For example: charge during the overnight off-peak window if you're on a time-of-use tariff.

If You Have an EV Charge Point

Make sure your EV charger is wired using a Henley block to split it off from your main household load. Without this, a car charging session could drain your batteries rather than drawing from the grid as intended. Post in the community if you need advice on how this should be set up.

Tests to Run Once the System is Live

Run these checks with your installer present before they leave. Some require sun or a charged battery — if conditions aren't right on the day, arrange for a follow-up visit.

1. Switch on the kettle and check your smart meter — if the sun is out or batteries are charged, there should be minimal grid draw.
2. Batteries may draw from the grid initially for a balance charge — this is normal for one day. If it continues beyond that, contact your installer.
3. If you have an EV, try a short charge session. Check it draws from solar (not batteries) if solar-enabled, and that no breakers trip when the charge stops.
4. If EPS/UPS was installed — ask the installer to simulate a grid outage and confirm appliances continue to run.
5. Check your monitoring app shows the correct direction of energy flow — solar generation, battery charge/discharge, and grid import/export should all be displayed accurately.
6. Check your smart meter is recording some export — virtually any system will export something.
7. Confirm the monitoring app shows batteries charging from surplus solar when the sun is out.
8. Confirm batteries charge during the off-peak overnight window (if configured).
9. After a clear sunny day, compare actual generation against the installer's estimated daily figure.
10. On a sunny day, check the generation graph for unexplained dips — these can indicate over-voltage or inverter overheating.
11. If a G99 export limit applies, confirm on a sunny day that export does not exceed the limit. If it does, the inverter may not have been configured correctly.

Documents to Receive Before Final Payment

1. DNO G98 notification (systems under 3.6 kW total inverter capacity) or DNO G99 approval (3.6 kW and above). Confirm the kit list on the document matches what was actually installed.
2. For G99 systems — written confirmation that the installer has notified the DNO of commissioning. Without this, you may be unable to obtain an export MPAN and will struggle to sign up for an export tariff.
3. MCS or Flexi-Orb certificate — confirm it matches what was installed.
4. Electrical installation certificate (Part P).
5. System schematic diagram.
6. Component serial numbers for all major equipment.
7. Warranty documentation and registration details.
8. Insurance Backed Guarantee (IBG) certificate — e.g. from HIES. Confirm it is an IBG and not just deposit protection.
9. Operating manualfor all components — covering how to switch the system on/off/reset, how to tell when it's running at full capacity, and how to change settings such as battery charge times.
10. All user IDs and passwords for devices, monitoring websites, and apps. Test them before the installer leaves.
11. Installer contact details for ongoing support.

After the Install — Final Steps

12. Register your equipment with the manufacturer — required to validate (and in some cases extend) your warranty.
13. Notify your home insurer — solar and battery storage may need to be declared as a change to your policy.
14. Apply for an SEG (Smart Export Guarantee) export tariff — compare rates across suppliers, as they vary significantly.
15. Consider an off-peak import tariff — if you have a battery, a time-of-use tariff (charging overnight at lower rates) can significantly reduce your bills further.