Prefabricated garage - concrete or steel? What is recommended?

A neighbor of ours has a plastered steel garage measuring 3x9m, it really looks awful.

I have a 9m long double steel garage, in which we also use the rear area universally for storage of garden tools, children's toys, bicycles, car accessories, tools, etc.

One main reason was, among other things, that we do not have 6m width available. In this regard, steel garages are of course significantly more flexible and space-saving.

Our steel garage stands on a U-foundation and is paved. At the beginning, we had moisture on the floor. Whenever I placed something down, the pavement underneath would be wet afterward. During that time, I also had rusting tools. But that settled after a while.

For dripping water from above, the manufacturers usually offer a coating. I have a friend who has a steel garage without this coating and told me that he occasionally has drops on the ceiling and on the car during unfavorable weather conditions. However, the number of days can be counted on one hand.

From my point of view, moisture can escape much better in a steel garage than in a precast concrete garage.

Where you have to think a bit more, in my opinion, is if you want to fix something to the walls. (Electricity/hanging for garden tools, etc.)

An advantage of concrete garages, from my perspective, is that the concrete garage should filter temperature peaks much better. Cold beer in summer you only have in a steel garage with a refrigerator :) and in winter it freezes. No idea what the experience is like with precast concrete garages.

In this respect, steel garages are of course significantly more flexible and space-saving.

A classic Bauwich garage allows an internal width of 290 cm, with the concrete version it's 282 cm – from my point of view, that's rather marginal. With the R129, one might notice the "difference" more than with the W124.

One advantage of concrete garages, in my opinion, is that they are likely to filter out temperature peaks much better.

Climatically, I am most satisfied with pumice. For storage, mind you. The cars from Opel to Ferrari have never complained about steel.

Where, from my point of view, you have to think a bit more is when you want to attach something to the walls. (Electricity/mounting for garden tools, etc.)

That is also a topic. We are planning a preparation for an electric charging station in the garage, logically with high voltage.

A classic building-line garage allows an internal width of 290 cm, with the concrete version it is 282 cm – from my point of view that is rather marginal. With the R129, one might notice the "difference" more than with the W124.

If you don’t have a beam at door height in the way, the difference between inside and outside width in our steel garage is almost marginal. Unfortunately, we only had 5.40 m of outside width available. Due to the dual usability of the central aisle for getting in and out and the significantly thinner outer wall, in the end we have somewhat more internal width available per car than a standard 3 m concrete garage.
Generous is of course something else.

Climatically, I am most satisfied with pumice. For storage, mind you. The cars from Opel to Ferrari have never complained about steel.

Ultimately, cars are made for outdoors. A carport makes it noticeably more comfortable, especially in winter. Everything else, whether solid masonry, precast concrete, or steel garage, is already luxury purely for the car.
If you want to store or do more frequent "DIY work" in it, the demands on the garage exterior increase.

That’s also another topic. We are planning a preparation for an electric charging station in the garage, logically with three-phase power.

When I recap your thread history, I can basically only give you the general advice to choose a smaller model from the GU’s catalog; in terms of area, I see potential there. Attempts at post-contractual rightsizing won’t make you happy in the long run. A "city villa" with patchwork from “we can still save on the garage” and various other extras postponed to future salary increases (wallbox, canopy, ...) will always look miserable compared to the initial drawings of how it should actually look. Better a E-Class with leather than an S-Class on steel wheels. It’s not like the house would immediately become too small. If you don’t dare to take this apparent step back, at least take the metal garage; it’s the cheapest to replace. Save yourself the nonsense with the concrete look. Or even better: leave out the garage entirely and just get the shed part for a carport. That way you keep the trash bins and winter tires out of sight, and the cars sleep outdoors. However, you can also combine this with the smaller house model – guilt-free without a concrete ceiling under the roof trusses.