ᐅ Barn Conversion into a 120 m² Residential Home – What Costs Are Involved?

Hello everyone,
we are currently in the process of purchasing a property with a 1000 m² (10,764 sq ft) plot. There is an old residential house and a well-preserved barn on the site. The residential house is planned to be renovated and rented out. The barn, about 120 m² (1,292 sq ft), is going to be converted into living space and occupied by ourselves.
I have identified three architects who specialize in historic buildings and barn conversions. We will be having on-site discussions with them soon.
Beforehand, I would like to know if anyone here has experience with such a project and what costs were involved. I have read that you should expect around 1000 €/m² (approximately 93 USD/sq ft). Most of the expenses are for insulation, heating, and utilities.
Maybe someone here has already completed such a project.

There is already a lot of discussion here about "normal" construction costs. I believe that with a project like this, the price range will vary even more.

Near us, someone converted a listed barn into a music store—and I mean really built inside it. It’s essentially a house within a house concept. The barn’s roof was waterproofed and reinforced, and the structure stabilized, but otherwise the exterior remained untouched (due to its listed status). Inside, complete rooms and levels were built using timber frame construction, independent of the barn itself. However, this project cost well over 1000 euros per square meter (approximately $110 per square foot).

I think you should wait for the three appointments first. Then you will have a clearer idea.

One tip: before you buy, you should clarify whether converting the barn into living space even has a chance of approval.

Thank you for your response.
I have checked with the district administration regarding the conversion of the barn into a residential building. This is possible. The building is not listed as a historic monument, even though it was built in 1785. There is no local development plan in the municipality, but the design guidelines apply. Since the barn borders on neighboring properties, this needs to be clarified beforehand. I think we will also need to insulate it from the inside, or a house-within-a-house concept could be considered.
We estimate the costs to be around 200,000€.

Roughly, you can simply estimate the costs based on a comparable new build.
What exactly is meant by a "very well-maintained" barn?
Probably just walls and a roof.
Demolition and a new build would likely be more cost-effective.

I would also refer to it as new construction costs. Usually, you can only reuse a few walls, but these mostly serve as decoration rather than protection. Good luck – an exciting project

Demolition is not an option for us. We specifically looked for a barn to convert. The roof is in good condition. Otherwise, it is a barn built with rubble stone. It is also not too large. We estimate a maximum of 100-120 m² (1,076-1,292 sq ft) floor area.