Celotex TB4000 is a high-performance PIR (polyisocyanurate) thermal bridging board designed to reduce heat loss at structural junctions such as steel beams, lintels, balcony connections and parapets. Available in thicknesses from 20 mm to 165 mm, it offers superior thermal resistance in a slim profile, helping buildings meet Part L energy-efficiency requirements.

Key Benefits

Application

Cut boards to size using a fine-toothed saw or sharp knife. Fix mechanically or adhesively to the structural element to be insulated. Ensure tight butt joints between boards and seal with foil tape to maintain vapour resistance. Position to break the thermal bridge between the internal and external building envelope. Refer to accredited construction details for specific junction detailing.

Coverage

Standard board size is 1200 mm × 600 mm (0.72 m² per board). Thermal conductivity: 0.022 W/mK. R-values range from 0.90 m²K/W at 20 mm to 7.50 m²K/W at 165 mm.