The last few years have seen Building Regulation guidance tighten significantly and the pressure is on architects to close the gap between designed and as-built performance. Knauf Insulation’s latest online tool has been created to help architects specify steel frame rainscreen façades, with that ‘real world’ performance in mind.

A UK first
Knauf Insulation has launched the UK’s first free online 3D U-value calculator , allowing architects to instantly generate more accurate U-values for steel frame rainscreen façade specifications. The tool is designed to help architects more closely reflect as-built performance in their designs and avoid costly over-specification.

Bradley Hirst, Technical Services Manager at Knauf Insulation, explained: “Ordinarily, architects might have to wait up to two days to get this information. Now they can use the tool at any time and get an instant result. And they can revise their designs as much as necessary to reach their target U-value”.

Why 3D calculations are important
Standard U-value calculations for rainscreen façades assume a default bracket configuration, applying a blanket correction factor for the build-up. This can lead to specifying needlessly thick insulation or result in a gap between designed and actual performance. The 3D U-value calculator works from the architect’s actual design to provide a more accurate result.

With regulations becoming increasingly stringent, the calculator helps architects ensure compliance by delivering a design more likely to perform as intended in the real world. The calculator also creates a detailed report that helps to meet regulations and protect the specification by showing the potential impact of inappropriate substitutions.

Further innovation
This is the latest in a series of innovations developed by Knauf Insulation to support rainscreen performance in the real world. In 2024, the manufacturer launched Rocksilk® RainScreen FFCB, the first cavity barrier that is fixed to the face of the insulation, and Rocksilk® RainScreen Slab EE, the UK’s first rainscreen slab with a water-repellent facing.

Speaking about the 3D U-value calculator, Bradley added, “We’re always looking for ways to make it as easy as possible for architects to design buildings that perform in the real world. In time, we plan to add masonry and reinforced concrete rainscreen façades to the tool, so that architects have instant access to 3D U-value calculations for a broader range of applications”.

Try the 3D U-value calculator here.