This article is all about why it’s better to save and do a high performance renovation, rather than incrementally adding lower levels of energy efficiency measures.
“the “lock in” effect is acknowledging that most buildings that undergo a moderately efficient renovation are not likely to be renovated again for another 50 years, given the financial strain on owners to recover the original renovation investment cost. In other words, you will not re-replace the windows in 10 years, even if you understand window specifications better then than you do now. Your replacement windows have “locked in” a moderate level of efficiency for the long term”
