What Changed
On 28 November 2025, MCS opened a consultation on MIS 3002, the Solar PV Installation Standard. This consultation gives installers and industry stakeholders the opportunity to provide feedback on proposed updates to the standard.
Standards consultations typically lead to refined evidence requirements. Installers can expect potential updates to roof assessment documentation, shading analysis, and electrical evidence requirements. The consultation provides an opportunity to influence outcomes by submitting feedback based on practical on-site experience.
- Consultation launched: MCS announced a consultation on MIS 3002 (Solar PV Installation Standard) on 28 November 2025. Source (MCS)
- Installer impact ahead: consultations often refine evidence requirements and documentation expectations, so survey workflows should be ready for tighter validation.
- Documentation focus: when standards shift, the quickest failures in audits are usually evidence gaps, not system design errors.
Timeline: Based on typical MCS consultation patterns, final standards updates usually follow 3-6 months after consultation closes. That means if consultations close in Q1 2026, updated standards could land by Q2-Q3 2026.
What to expect: MCS consultations typically focus on evidence quality, documentation standards, and audit requirements. For solar PV installers, that usually means tighter roof assessment documentation (more detailed photos, clearer shading analysis, better structural notes) and stricter electrical evidence (spare capacity calculations, cable routing notes, DNO requirements).
The safest response is to tighten evidence quality and traceability now, so any updated requirements can be met without rescheduling surveys. That approach is also customer-friendly—when evidence is gathered once and stored cleanly, there's less risk of post-install queries that slow down payments or handovers.
Why Installers Care
Solar PV projects already require a clean chain of evidence: roof condition, shading context, layout decisions, and electrical integration. If the standard tightens or clarifies evidence requirements, installers who are not already capturing high-quality survey data risk rework.
Consultations tend to focus on the most frequent points of disagreement in audits: unclear roof notes, missing shading context, or electrical details that do not match the declared design. Those are the gaps that create the most installer pain.
From an installer point of view, the two biggest operational risks are:
- Survey evidence requirements: missing roof photos, unclear roof construction notes, or partial electrical documentation can cause delays at sign-off.
- Callbacks and rework: a follow-up visit for missing photos or paperwork costs margin and disrupts the install schedule.
- Customer confidence: solar customers expect speed; delays caused by evidence gaps feel like poor planning even when the install team is ready.
The consultation is a reminder that evidence standards can move. A disciplined survey pack protects you against policy shifts without slowing your install pace.
In practice, this means your survey team should be aligned with your design team. When the survey pack is comprehensive, the design can be signed off quickly and the install crew can trust the documentation.
It also simplifies customer communication. When a homeowner asks why a design choice was made, you can point back to documented roof and electrical constraints rather than re-explaining assumptions.
What to Capture on Site
To keep solar PV installs audit-ready, capture evidence that clearly supports the layout, mounting approach, and electrical connection decisions. The goal is a pack that a third-party reviewer can understand without guesswork.
Think of the evidence as a narrative: where the array sits, why the layout was chosen, and how the system is safely integrated into the property. When a reviewer can see that narrative, compliance checks are smoother.
- Roof photos: full roof planes, ridge lines, eaves, obstructions, and access points.
- Shading context: photos showing nearby trees, chimneys, or adjacent buildings that could affect yield.
- Roof construction notes: tile type, structural notes, and any visible constraints that affect mounting.
- Electrical evidence: consumer unit location, spare capacity, and cable routes.
- Inverter and equipment locations: intended siting, ventilation clearance, and access for maintenance.
- Documents on the day: EPC (if available), planning or conservation notes, and any prior electrical test certificates.
RdSAP evidence documents should be photographed on the day when applicable, even for solar-only jobs where EPC updates may be required later.
If a homeowner does not have documents available, record that clearly in the notes. It is better to show a documented gap than to leave the pack silent.
Evidence Quality Standards
For solar PV installations, consistent evidence capture helps ensure smooth compliance checks. Key elements include:
- Organised photo structure: photos grouped by area and context for easy review
- Clear evidence notes: documentation that supports layout, mounting, and electrical decisions
- Complete documentation: all relevant evidence captured during the survey visit
- RdSAP evidence documents: photographed on the day when applicable
As MIS 3002 evolves, comprehensive evidence capture helps installers adapt to updated requirements without needing to resurvey properties.
Timeline & Action Plan
What to do now:
- Submit consultation feedback: MCS wants installer input on what's practical on-site. Use this chance to influence outcomes (consultation typically closes 4-8 weeks after launch)
- Audit current evidence workflows: review your roof assessment documentation, shading analysis, and electrical evidence to identify gaps before standards tighten
- Prepare evidence templates: tighten photo requirements, clarify note-taking standards, and standardise documentation formats so updated requirements can be met without process changes
- Train survey teams: ensure surveyors understand what evidence MCS typically focuses on (roof condition, shading context, electrical integration) so evidence quality improves now
What to expect next: Based on typical MCS timelines, updated MIS 3002 standards are likely to land by Q2-Q3 2026 (3-6 months after consultation closes). The consultation provides installers with an opportunity to prepare for potential changes and ensure their evidence workflows align with evolving standards.