Key legal question
Whether the demolition of the upper and attic floors and the new concrete slab qualify as deductible maintenance costs for the 2015 cantonal and federal taxes.
Extracted holding
No. The works were an economic new build / total renovation of the relevant parts, so the expenses were value-enhancing investment costs rather than maintenance.
Extracted reasoning
Maintenance preserves existing value; here the old superstructure was demolished and replaced by a new structural element, the insurance value rose significantly, and the works were necessary for a later rebuild. Under objective-technical criteria, the entire complex of works had to be treated as value-enhancing.