As with balconies, continuous parapets are prone to the problems of thermal bridging because energy is transferred through the thermal barrier. The conventional method of insulating parapets is to wrap the perimeter of the wall with an insulation barrier and, by wrapping the parapet, it becomes part of the heated building mass. However, the Schöck Isokorb type AXT provides a more thermally efficient and cost-effective alternative. It sits outside the heated building mass, separating the parapet at ceiling level and thereby reduces the energy loss significantly.
The Isokorb type AXT has an insulation thickness of 120mm, resulting in low psi values and tests show(1) that the heat loss reduction is significant. Its Performance is also certified as suitable for Passive House design, therefore satisfying the most stringent energy standards. In addition, a recent independent construction cost comparison(2) was undertaken involving two parapets each 12.5m long.
One was a conventional parapet construction detail and the second incorporated the Isokorb type AXT. This showed that in construction cost terms alone, the Schöck alternative comfortably achieved savings of up to 10 per cent, depending on the structure. Other benefits are that as no wrapping is required, the type AXT permits a more sophisticated construction opportunity with greater freedom of design.
There is no risk of any additional thermal bridging through balustrade fixings, the solution is impermeable to water and requires no maintenance, so there is no risk of expensive restoration due to waterproofing problems. In addition to being a “Certified Passive House Component”; the AXT provides BBA Certification; LABC Registration; NHBC approval – and meets full compliance with the relevant UK building regulations and many projects in the UK are already benefiting from this exciting new innovation by Schöck.
(1) (2) For a detailed breakdown of the performance and independent cost comparison results and a free copy of the new Schöck AXT Parapets Brochure – contact the company on 01865 290 890 or visit www.schoeck.co.uk