Concrete driveway cleaning and patching

A nozzle with a wider dispersion pattern would be essentially the same as taking your existing nozzle and backing off the distance a bit. If backing off results in inadequate cleaning then you don't have a powerful enough washer.

That is mostly the advantage of using a more powerful (PSI) washer. That you get the same cleaning effectiveness with a wider pattern so that the job takes less time.

Yes you want a different nozzle. You may need more power (both psi and gpm) with the wider nozzle.

Low pressure or low gallon-per-minute pressure washer, with too fine a nozzle. The ones that clean faster cost more.

Its because the pressure washer you are using isn't powerful enough. Better of getting a prefessional driveway cleaning company in. If your in Bromsgrove, check out

Geez a spammer dragging up really old post to advertize his company

I have to kick myself in the nuts, but thanks for responding.

Yours, and mine own, point is rather irrelevent.

LOL! Grammar check that!