Scaling to a single family residence application, it only needs a 4” wide trench dug down about 3-4’ in the climate zone of south OK and north TX where my cousin does business at. The back yard is definitely torn up during install though because a couple of hundred feet of polypropylene tube is lateraled back and forth in a closed loop with a pump and a shell and tube heat exchanger adjacent to the outdoor heat pump.
The install crew is generally onsite 2-3 days. Factors that extend the on-site time are rock breaking and if restoring the back yard via fine grading and lawn reseeding/sodding is in the scope of work. A local licensed electrician is also needed to install the pump power and relay interface to the HVAC.
A couple of hundred feet of trench opening, rolling the polypropylene tube in and covering can be done in one day unless dealing with significant rock breaking. Polypropylene tube in this scale of application usually does not need bedding because a tight leveling tolerance is not needed and the crush resistance far exceeds the loading. Soil shifting over time is very unlikely to exceed the bending capacity of polypropylene and there are no buried fittings for tree roots to weasel through.
Polypropylene tube rated for underground duty is used. No crappy Sch 40 PVC, I hate the stuff. Sch 120 PVC pipe rated for buried duty is more expensive than polypropylene. Metal pipe has much better heat transfer than polypropylene but has a finite service life or is way expensive. Polypropylene tube is one and done and will last longer than the house.
I imagine scaling of the ID with polypropylene is far slower and lower accumulation than any metal pipe, too (even with water treatments on the secondary side.
I use it for drip irrigation. It is amazing stuff.