New construction is increasingly being built to meet the maximum level of the Code for Sustainable Homes (previously EcoHomes) scheme. This is a points based environmental rating scheme used to illustrate the quality of the overall site design. It was created by the Building Research Establishment.

Maximum credit points for boilers are earned when NOx (nitrogen oxides) emission levels are less than 40 mg/kWh dry air free. This level exceeds the best required by British Standards, usually referred to as Class 5.

The Ideal HE range of SEDBUK A appliances has been fully tested in conformance with the relevant Standards to establish weighted values taking into account the boiler modulation, and all boilers now achieve NOx levels of less than 40mg/kWh. These results have been independently verified by Advantica.

Therefore the following boilers: Esprit HE, elise H, icos HE, isar HE, icos system HE and istor HE will achieve maximum credits under the Code for Sustainable Homes scheme.

Measured results are as follows:

Model	NOx (mg / kWh)*	NOx (ppm)*
icos HE12	15.5	8.8
icos HE15 icos System HE15 elise H15	16	9.1
icos HE18	13.3	7.5
icos HE24 icos System HE24 elise H24 esprit HE24 esprit HE30 isar HE24 isar HE30 istor HE260 istor HE325	19.2	10.9
esprit HE35 isar HE35	17	9.6
icos HE30	19.7	11.2
icos HE36	24.5	13.9

* All figures are quoted at dry at 0% Oxygen.