In UK the "house" ground is usually connected "earth" and connected to neutral at the substation (transformer for the locality). In Ireland there is supposed to be a 1.5m approx galvanised earth spike near the meter box or grid input and the neutral and earth are bonded there. That's quieter.
Maybe 50 years ago people might have used the water pipe as an RF earth, but that might be plastic. You're not supposed to use any utility pipes, central heating pipes etc as a radio Earth.
Don't connect your own Earth spike to the mains supply Earth. They need isolated, especially on the UK system as large currents might flow. The exception might be if your neutral and earth are bonded at the meter box and go to a nearby earth spike and there is no utility company earth.
Every non-loop aerial has a "counterpoise" even if you can't see it. A vertical needs either to be driven at earth level, or have 1/4 wave or more radials or counterpoise, or a sleeve that is earthed only at drive point with an internal diameter ratio with coax outer diameter to give the 50 or 75 Ohms. An unfolded, non-loop, dipole obviously has a "counterpoise".
The end fed Zepp (so called because used on the Zeppelins as a radio aerial) doesn't seem to have a counterpoise, but has really, on the modern version the feed line is the counterpoise.
Similarly the over hyped G5RV is only a proper dipole at one narrow band, otherwise the feed cable is the aerial (and partly counterpoise) and then the counterpoise is really the shack earth.
The thing to avoid is an exactly half-wave radiator or counterpoise as that has a very high impedance.
Mike EI9FEB