Be aware of higher rental value
Even if you replace a leaky flat room with a pitched roof while adding an extra room at the same time, the tax authorities will view that as an increase in value and refuse a tax deduction. On the other hand, additional rooms and a pitched roof may result in an increase in the official and rental value. Access and connection fees and individual refuse collection, water and electricity charges are also excluded.
Other non-deductible costs include: motoring costs, office rental, construction project, mortgage set-up and property valuation charges. Notarial documents, mortgage certificates, surveying costs, agency commissions and architect’s fees on projects not carried out also cannot be deducted.
With low rental values or high maintenance costs, the deductions can be higher than the rental value. All cantons accept this, but Basel-Stadt, Geneva, Glarus, Neuchâtel and Uri apply restrictive provisions.
To distinguish between maintenance and value-adding investment costs, most cantons have issued factsheets outlining the main deductions.