Upgrade outdoor water tap from ½ to ¾ inch

Hello,

our outdoor water tap is connected to a ½ inch wall penetration and behind it there is a Grundfos MQ 3-45, which draws water from a well outside the house. Since the ½ inch is of course not ideal, I am considering upgrading the wall penetration from ½ to ¾ inch. However, it is not clear to me how the outdoor water tap was attached and how I can replace it and the pipe of the wall penetration without damaging the exterior wall. It is definitely a wooden stud wall with Fermacell, polystyrene insulation, and silicone resin plaster.

Could you possibly give me a tip on how I, as a layman, can implement this without damaging the exterior wall and especially the visible plaster?

Here are a few pictures of the situation.



Regards Jochen

The tap valve can actually be unscrewed from the wall like that. Then a transition piece from half to three-quarter inch and done. However, your purpose is not clear to me, You’re not going to feed well water into the house line, are you?

The well is outside, the pump is frost-proof inside the house, and the water connection is led through the exterior wall to the outside with 1/2 inch. Now I want to connect an irrigation system there, and 3/4 inch would of course be much better for that. So I want to eliminate the 1/2 inch bottleneck, but I don't know how the old installation was secured and how I can get it out of the wall.

Then you will have a problem, presumably this will not proceed without visible damage. The pipe will certainly be secured somehow and somewhere within the building envelope. Otherwise, it would have to move and wobble every time the tap is operated. For a three-quarter inch tap valve, the hose connection would then also be one inch.

If it is only a type of flange that has been screwed onto the insulation, that is, under the plaster, it would not be so critical, but if it is attached to the Fermacell wall behind the insulation, I probably really have a problem. Possibly I could still increase the flow rate a bit if I replace the fitting in the house (see picture 3) with another version. What is currently installed there seems to be smaller than 1/2 inch at the 90-degree angle. Would that possibly help a bit, and can it simply be replaced there?

The fitting is pressed with a machine
a replacement is no longer possible for reasons of space
the fitting would also have to be cut off from the [Verbundrohr] which would make the pipe too short.
What remains would be an additional new penetration.