I see we're low on time.
I think it's a question you should put to the manufacturers and distributors of those devices. We buy them, and we buy the best ones we can. I'll be doing it in my own private home pretty soon, as I was saying before.
My point about the existing building always being the greenest is just that if you want to solve the problem, you can't just look at future buildings being built. Whatever metric you use—the number of buildings in five, 10, 50, or even 100 years—almost all of them are already built, so you have to look at the operation, maintenance, and retrofit of the current stock as well.