MCS Certified Solar Installer London — Why It Matters

NICEIC certifies competence in BS 7671 wiring regulations and Building Regulations Part P — it covers the electrical-installation side of any work in a domestic property. MCS certifies competence in renewable-microgeneration install and commissioning under the relevant MIS standard (3002 PV, 3012 battery, 3005 ASHP). A solar install needs both: NICEIC for the electrical compliance and MCS for the renewable-system compliance. The same firm can hold both, which is the typical pattern in 2026.

Yes — and that is the usual setup for a competent London solar installer. The two schemes audit different aspects of competence and are not in conflict. Our firm is NICEIC-registered for the electrical side and partners with MCS-certified solar / battery / ASHP install teams under the MIS umbrella project numbers. Customers receive both an NICEIC installation certificate and the MCS certificate at handover.

MCS Certified Ltd, the scheme operator, oversees an approved set of Certification Bodies — currently NAPIT, NICEIC EPVS, Trustmark, RECC and others. The installer chooses a Certification Body, pays the annual scheme fee, undergoes an initial audit against the MIS standard for the technology, and renews annually. Every install is registered on the MCS database — searchable by certificate number on mcscertified.com.

Search the installer’s MCS number at mcscertified.com — every certified installer is publicly listed with the technologies they are certified for and the current expiry date of the certification. Cross-check the company name, address and director against Companies House and against the NICEIC online register. Ask for the most recent MCS audit date — it should be within 12 months.

Annual. The MCS certification is reviewed and renewed every 12 months via the chosen Certification Body, with a desk-based audit covering recent installs, complaints, financial standing and continued compliance with the MIS standard. Lapsed certification disqualifies subsequent installs from SEG and BUS — so the renewal date matters when you are signing a contract.

Persistent non-conformance with the MIS standard, failure to lodge installs on the MCS database within the required timeframe, customer-complaint volume above threshold, financial difficulty (the insurance-backed workmanship warranty depends on the installer remaining trading), or audit failure on a sampled install. Loss of MCS would block your install from SEG and BUS — which is why the workmanship-warranty insurance is a critical layer.

First raise the issue directly with the installer — they have 8 weeks to investigate and respond. If unresolved, the consumer code (RECC or HIES) operates a TSI-approved alternative dispute-resolution scheme. Beyond that, escalation routes through MCS Certified Ltd directly for technical non-compliance, the Certification Body for installer-conduct issues, and Trading Standards for consumer-protection breaches.

EAS is the consumer-information service for low-carbon home energy — it points consumers to MCS-certified installers, explains scheme eligibility (SEG, BUS, ECO4) and provides independent advice on technology selection. It is run by Energy Saving Trust on behalf of DESNZ. Useful for consumers researching their first solar install before approaching installers directly.