At least where I live it's the historic houses that are worth more than the newer ones, partly because there's a limited supply of them, but partly because the

At least where I live it's the historic houses that are worth more than the newer ones, partly because there's a limited supply of them, but partly because the desirability of a house often has little to do with what's "efficent". Further limiting the supply by reducing the number of them is only going drive such house prices up. I'd also note there are plenty of cities with massive housing affordability problems but little in the way of historic buildings (Hong Kong, San Jose & much of SV etc.). Even in my own city (which often rates as one of the least affordable for housing), historic buildings make up a small percentage of total housing.