Klober Permo® therm is a Kooltherm® insulation board with tongue and groove edges, integrated underlay and self-adhesive edge strips for sealing laps. With full LABC approval, it is suitable for all pitches but, unlike square-edged boards, won’t provide an air leakage path.
Permo therm is installed over the rafters and therefore provides added height within the roof space. 80 mm thick, it can be laid on boarded or un-boarded roofs, either from left to right or right to left. No ventilation of the batten/counter-batten cavity is needed with most tiles or slates as these are considered to be air-open but for impervious or tight-fitting roof coverings ventilation should be provided.
Fittings are available to ensure correct installation, thermal performance and airtightness, a good example being a Universal Roll for dressing over ridges, hips, valleys, verges and abutments.