Solar · For traders
What does MCS 012 require of roof hooks and fixings on tiled or slate roofs?
Short answer
Pitched-roof kits must be certified to MCS 012. Issue 3.0 has been mandatory since 10 May 2025. Hooks on tiles or slates must either put no load on the covering or be tested to spread load evenly without damage. Tiles must be notched or flashed so no new gaps appear, and sealant-only weathering is not certifiable.
Last checked 24 September 2026 · 1 source
In more detail
- MCS 012 cl.7.7.2 test loads: >=1.0 kN/m2 for systems, >=0.25 kN per individual hook; load-spreading hooks must not be stood on.
- MIS 3002 cl.5.3.1 disapplies CoP 11.4.1 no-load rule only for hooks certified under 7.7.2(b).
- MIS 3002 cl.5.9.8 notch or flash tiles; 5.9.9-5.9.10 metal roofs: sheet thickness and fixing checks.
- Use only components approved to work together; kits certified with named modules only with those modules (MIS 5.5.3-5.5.4).
- Roof warranty: consult provider; written customer agreement if warranty may be invalidated (MIS 5.9.2-5.9.3).
The facts, dated
- 01MCS 012 Issue 3.0 mandatory for certified products — 2025-05-10 date
standard · UK · checked 24 September 2026 · MCS
- 02Minimum downward test load for a single load-spreading roof hook — 0.25 kN
standard · UK · checked 24 September 2026 · MCS
What we saw in the field
[QA review 2026-09-24] I-12 AGREES. | Earlier notes: Installer claim that roof damage comes from bodged installs (lifted tiles, flashings, hooks into structure) agrees with MCS 012/MIS 3002 emphasis on certified hooks, flashing and structural fixing.
Sources
Last checked: 24 September 2026