London -- ISO-Chemie's expanding polyurethane foam tape is being used in a research project at the University of Bath looking into the feasibility of constructing buildings from straw bales.
The tape, called ISO BLOCO One is being used to provide a high-performance airtight, acoustic and thermal seal between the straw-filled, cassette-style building blocks used to construct the two-storey BaleHaus at Bath on the University's campus, said a 1 June announcement.
The BaleHaus is a research building constructed using the ModCell system to assess the use of straw as an efficient, effective and long-term building material.
The system exploits straw's excellent thermal insulation qualities, with hemp construction to form prefabricated panels. According to a press statement, these "can allow super-insulated, high-performance, low-energy 'passive' buildings to be constructed using renewable, locally sourced, carbon sequestering materials."
As a result, buildings can be constructed to meet the demanding PassivHaus specification, with zero heat requirements, saving money and CO2 emissions.
Strips of ISO BLOCO One have been installed in the 10mm expansion joints between the 3 sq.m bale blocks to form an airtight seal (0.86 cu.m/hour/sq.m at 50 pascals), with the construction industry norm at 3 - 5 cu.m/hour/sq.m, said ISO-Chemie.
Peter Thompson, ISO Chemie's UK general manager, said: "Increasingly, systems like Modcell are being considered as low-cost, practical and very sustainable building products for construction projects.
The manufacturer claims that ISO BLOCO One offers a 'fit and forget' solution for fast and effective sealing based around the principles of three-level sealing. The inside seal area is more airtight than the external one, allowing any trapped moisture inside the joint, or within the wall, to escape outwards rather than into the building.
The external seal area provides weather resistance and breathability, while the intermediate seal area provides extra thermal and acoustic properties and the internal one air tightness and humidity regulation. All three levels are designed to accommodate movement between the adjacent materials, said ISO-Chemie.