My first thought is get someone else to do it - only joking... There's three options: a high pressure hose (with a hose extension) and a ladder - climb to the roofline and let the high pressure hose do the work - you might have streaks - but you will after the next rain anyway OR use a magnetic window cleaner OR use a long extension handle on a regular window cleaning squeegee (video link below).

I do a thorough job weekly, but my partner has way higher standards of cleanliness and I do find him washing the sink and cleaning the shower doors on a daily basis. If he wants to do that, I don't complain about it. :)

our obsession with antibacterial products apparently is creating bacteria which are resistant to antibiotics. They should be banned if the government could take any decisive action (not talking about general disinfectant here, just every surface spray for the kitchen and hand washing that also "needs" antibacterial)......

This is an interesting thread - whilst I agree that the distinction between "chemical" and "non - chemical" may not be the most useful one (for the reason pointed out above) - maybe a more useful discussion is about harmful and less harmful cleaning substances, whether to the environment or people. I suffer from something called MCS ( multiple chemical sensitivities, it's a diagnosis) and have come to realise that in my case at least it's not chemicals per se that make me sick, but rather certain smells. For example I cannot have the "Earth choice" (a natural") brand floor cleaner used in my house without suffering a few days of sore eyes, nasal congestion, fatigue, foggy brain and sinus headaches - it is truly debilitating, and the cause is the fragrance. If I use the same brand of "Naked" ( no scent) dish cleaner diluted on the floor instead, I am fine. I think everyone with MCS is different but this is working for me.