Ireland has released its nearly-zero energy buildings regulations (to comply with EU requirements) and insulation supplier Xtratherm has published a guide for builders/designers. I’ve pulled together a table of the minimum performance values and calculated the R-values to help folks in NZ compare. These are average values and include thermal bridging from timber etc.
Note that although the climate in Ireland is a bit colder than Christchurch, the heating energy is only about 20-30 % more per year for the couple of buildings I checked.
—9 Jan 2020