{"id":61298,"date":"2019-08-05T12:30:56","date_gmt":"2019-08-05T11:30:56","guid":{"rendered":"https:\/\/www.pbctoday.co.uk\/news\/?p=61298"},"modified":"2019-08-02T13:51:11","modified_gmt":"2019-08-02T12:51:11","slug":"insulation-specification","status":"publish","type":"post","link":"https:\/\/www.pbctoday.co.uk\/news\/building-control-news\/insulation-specification\/61298\/","title":{"rendered":"Addressing hidden costs in insulation specification"},"content":{"rendered":"

Kingspan Insulation has published a new white paper with research from Currie & Brown exploring how different insulation specifications impact overall project costs<\/h2>\n

With the government committing the UK to achieving net zero greenhouse emissions by the middle of the century, the race is on to tackle our built environment. Estimates suggest that the heating demand for buildings and industry accounts for almost a third of the UK\u2019s total greenhouse emissions. One obvious way to address this demand is by improving the insulation performance of building envelopes. These materials require little or no maintenance and, when installed with care and attention, can effectively minimise energy demand for decades.<\/p>\n

As with all aspects of a construction, the upfront cost of materials is a clear consideration in the specification process. As you might expect, the drawback with cheaper insulation materials is that they are less thermally efficient. This means that greater thicknesses are required to achieve a desired U-value and this change can have significant implications for other aspects of the build.<\/p>\n

Research from leading consultant Currie & Brown has now suggested that by specifying more thermally efficient materials in cavity wall<\/a> applications it is possible to reduce overall project costs while achieving slimmer construction thicknesses.<\/p>\n

Insulation options<\/h3>\n

Regulatory guidance on the level of thermal insulation required for new homes is covered within Approved Documents L1A to the Building Regulations 2013 (in England), 2014 (in Wales) and Section 6 (Energy) 2015 of the Building Standards in Scotland. To ensure compliance, it is a good idea to target an external wall U-value of 0.16\u00a0W\/m\u00b2\u00b7K for properties in England and Wales and 0.15\u00a0W\/m\u00b2\u00b7K in Scotland.<\/p>\n

A key measure of an insulation material\u2019s<\/a> performance is its thermal conductivity (lambda). Products with a lower thermal conductivity are more resistant to heat loss through conduction, meaning a reduced thickness of insulation can be used to achieve a desired level of thermal performance.<\/p>\n

Cheaper materials often have relatively high thermal conductivities. For example, mineral fibre insulation typically achieves values of between 0.032-0.037 W\/m\u00b7K. In contrast, the latest phenolic insulation boards have a thermal conductivity of just 0.018 W\/m\u00b7K.<\/p>\n

As such, while these boards are more expensive than lower performing materials, they can enable target U-values to be reached using thinner insulation, reducing external wall construction depths.<\/p>\n

To understand how this may impact overall project costs, Kingspan Insulation commissioned Currie & Brown to carry out an analysis.<\/p>\n

Cost analysis<\/h3>\n

To assess how the choice of insulation could impact overall project costs, Currie & Brown developed scenarios for properties of three different scales:<\/p>\n