When installing Mannok Therm Roof / MR above the rafters on warm pitched roofs consult BS 5534 Code of practice for slating and tiling (including shingles) – Annex B for guidance on calculation methods and fixings.

1. Install a timber stop batten across the rafters as shown in position C, with the batten equalling the thickness of the Mannok Therm Roof / MR insulation.

2. Lay Mannok Therm Roof / MR insulation boards above the rafters, butted tightly against the stop batten and supported on both sides by the rafters. If required, cut the insulation boards to ensure they fit tightly and secure temporarily with appropriate nails.

3. Install the vapour open underlay over the layer of insulation. The underlay should be vapour open (vapour resistance <0.25MNs/g) but water resistant, to protect against wind-driven rain and snow.

4. Install counter battens over the vapour open underlay along the layer insulation, with each counter batten in line with the position of the rafters beneath. The counter battens should be nailed to the stop batten previously installed.

5. Using the calculated fixing requirements specific to your design, install the fixings along the counter batten at maximum 400mm intervals.

6. Fix tile battens and roof covering over the counter battens.

7. On the internal side of the roof, fit a vapour control layer the insulation and the internal finish.

8. Finally, install the internal finish, such as plasterboard.