R-value (insulation) contain no trapped CFCs or HFCs (e.g., half-pound low density foams). On certain brands, twenty-year tests have shown no shrinkage or reduction in insulating value. This has led to controversy as how to rate the insulation of these products. Many manufacturers will rate the R-value at the time of manufacture; critics argue that a more fair assessment would be its settled value. The foam industry adopted the LTTR (Long-Term Thermal Resistance) method, which rates the R-value based on a 15-year weighted average. However, the LTTR effectively provides only an eight-year aged R-value, short in the scale of a building that
Design quality indicator Design quality indicator The Design Quality Indicator (DQI) is a toolkit to measure, evaluate and improve the design quality of buildings. Development of DQI was started by the Construction Industry Council (CIC) in 1999. It was initiated in response to the success of Key Performance Indicators devised for assessing construction process issues such as timely completion, financial control and safety on site by the construction industry's Movement for Innovation (M4I). The aim of the DQI systems was to ensure that the M4I's indicators of construction process were balanced by an assessment of the building as a product. The Science Policy