Flat roof insulated with termPIR AL panels — | BOKKA
Flat roof insulation with termPIR® AL panels — project by Hurtbud Seweryn Jański
Project overview
The scope of work covered the thermal insulation of a flat roof using PIR insulation boards. The installation was carried out by Hurtbud Seweryn Jański, a contractor specialising in comprehensive roofing services and the application of polyurethane insulation systems for building envelopes. BOKKA, as the regional distributor of termPIR® across Poland, supplied the panels to the site and provided full technical support throughout the project.
Design challenge
Flat roofs are among the most demanding building envelope components — they must simultaneously meet the stringent thermal transmittance requirements of WT 2021 (U ≤ 0.15 W/m²K), ensure full vapour-tightness and provide mechanical resistance to live loads and maintenance traffic. An additional design criterion is minimising the thickness of the insulation layer, which reduces the dead load on the structural deck and shortens installation time — a particularly important factor in commercial and industrial buildings with large roof areas.
Selected product — termPIR® AL 120 mm
The roof was insulated with termPIR® AL panels of 120 mm thickness. This is a PIR board faced on both sides with gas-tight aluminium foil, achieving one of the lowest thermal conductivity coefficients on the market at λD = 0.022 W/(m·K). The aluminium facing also acts as an integral vapour barrier, eliminating the risk of moisture ingress into the polyurethane core throughout the roof’s service life. The panels were mechanically fixed to the deck using a standard flat-roof build-up, with overlapping joints to limit thermal bridging. termPIR® AL is classified in fire reaction class E.
Final result
The use of thin, lightweight PIR panels delivered a high level of thermal performance while maintaining a slim insulation profile. The rigid polyurethane core combined with the aluminium facing ensures long-term durability and stable thermal parameters over the entire building life cycle — making termPIR® AL an optimal solution for flat roofs in modern construction, both in new-build and refurbishment projects.
