R-value (insulation) as ASHRAE 90.1 and the IECC prescribe U-values. However, R-value is widely used in practice to describe the thermal resistance of insulation products, layers, and most other parts of the building enclosure (walls, floors, roofs). Other areas of the world more commonly use U-value/U-factor for elements of the entire building enclosure including windows, doors, walls, roof, and ground slabs. The SI (metric) unit of R-value is whereas the I-P (inch-pound) unit is For R-values there is no difference between US customary units and imperial units, so the same I-P unit is used in both. Some sources use ″RSI″ when referring
Construction industry of the United Kingdom Construction industry of the United Kingdom The construction industry of the United Kingdom contributed gross value of £64,747 million to the UK economy in 2004. The industry employed around 2.2 million people in the fourth quarter of 2009. There were around 194,000 construction firms in Great Britain in 2009, of which around 75,400 employed just one person and 62 employed over 1,200 people. In 2009 the construction industry in Great Britain received total orders of around £18.7 billion from the private sector and £15.1 billion from the public sector. While manufacturing in the United Kingdom shrank as a proportion of