By Chris Knowles, Business Manager VIPS, Recticel Insulation
Technical innovation has taken insulation products, PIR panels in particular, to unprecedented levels of thermal performance and usability. For instance, the precision-cut tongue-and-groove joint that features on all four edges of Recticel’s rigid full-fill panel, Eurowall®+ ensures the boards lock tightly together, minimising heat loss through thermal bridging. The panel is capable of achieving a U-value of 0.18 W/m2K in a traditional 100mm masonry cavity wall, with the 10mm gap making for a more convenient fit for installing bricklayers.
In terms of flat roofs, the development of single-layer tapered insulation systems – such as those supplied by our tapered insulation division Gradient – have advanced the performance of flat roofs by providing a quicker, more accurate and flexible way of achieving of thermal performance combined with a degree of fall for roofing projects.
Whatever the benefits of certain products, long-term thermal performance requires good planning and specifying a suitable insulation system for a property to achieve the required U-value.
U-value calculation
The importance of maintaining good practice in respect of U-value calculation should not be underestimated. Failure to comply with standards during the process potentially jeopardises homeowner safety, results in higher fuel bills and is damaging to the environment.
When it comes to achieving U-values for domestic new-build projects it is a requirement to discuss stipulated outcomes with an energy consultant who can give advice based on the Standard Assessment Procedure (SAP). With this methodology, the thermal ratings of walls, floors, roofs, junction details and any renewable technologies are put into a metaphorical mix, the performance of which must correspond with or exceed the required regulations for the building. These elements can be changed, as long as the property achieves the required dwelling performance. The alternative to carrying-out the SAP assessment is to work on the notional dwelling specification, which has to be followed as a minimum to achieve a pass. Working to backstop values only, however, will result in failure.
Pre-installation good practice includes a contractor carrying out a survey of the building itself. Issues can occur when the insulation system is ordered on the strength of the architectural drawings, but it transpires that the property is constructed differently.
Additional preparation
Prior to installation work, basic care and attention should be paid as to how materials are stored. For pitched roofs or floor applications involving Eurothane GP boards, if left loose-laid unfixed in cool temperatures there is potential for the boards to warp due to the differential floor-air temperature. Although extremely rare, this generally occurs when the temperature is about 5-degrees or lower. Installers should therefore ensure all boards are laid as close to the screed/slab installation as possible.
Correct product selection is another ‘best practice’ essential for installation preparation to pay-off in the form of a well-insulated, thermally-efficient property. The Code for Construction Product Information (CCPI) will assist in improving this process by helping manufacturers drive higher standards in the presentation of building product information. Recticel is a huge advocate of this initiative, which prioritises building safety and quality. Setting out a product’s terms of use and intended outcomes clearly will not only inspire confidence in the user, it could help close the much-maligned performance gap and ensure properties are built as-designed.
Trusted, reliable manufacturers such as Recticel remain focused on improving levels of insulation performance to not only uphold their industrywide reputation for quality and ingenuity, but to help create a healthier, more sustainable built environment for generations to come. It is proof that best practice permeates every aspect of our culture, including our ideology.