U-Value Optimisation

Offsite construction techniques have the potential to deliver homes that are built to higher sustainability standards and reduce energy-in-use. Partel can assist design teams to develop fabric first solutions through U-value performance reviews to ensure the fabric build-up of individual building elements – walls, roofs and floors – are fully optimised from the outset.

A U-value calculation is used to determine the rate of heat loss through a building element. There are two main factors that determine the U-value of a building element; the thickness of materials used and the thermal conductivity of those materials. However, U-value calculations become more complex when accounting for repeating thermal bridging (studs), fixings, gaps in insulation layers, flange thicknesses (in metal frame systems) and reflective foil membranes.

Each construction type has specific complexities, and in Partel the technical team have experience in calculating U-values for masonry systems, timber frame systems, light gauge steel systems (LGS), structural insulated panels (SIPs) and hybrid systems. This experience allows the team to accurately calculate the U-value of a proposed building element and make suggested alterations to achieve the target U-value in a more cost effective, or easier way.

Where applicable, the ECHOFOIL range can be used to enhance u-value figures, without the need for additional insulation. ECHOFOIL EXO and ECHOFOIL IZO are known as reflective membranes. This means that as well as being airtight, and having appropriate Sd values, the membranes can enhance the R-value of an adjacent cavity from 0.18 m2K/W to 0.78 m2K/W – the equivalent of more than 15mm of PIR insulation. If you would like to see the impact ECHOFOIL membranes can have on your building elements, please feel free to request a free u-value calculation.

The Partel technical team use a U-value calculation methodology that is approved by the Building Research Establishment. Therefore, our u-value calculations can be used in DEAP and SAP, with required evidence provided for the energy assessor.

The Partel technical team use a U-value calculation methodology that is approved by the Building Research Establishment. Therefore, our U-value calculations can be used in DEAP and SAP, with required evidence provided for the energy assessor.