Sound insulation in case of a zoning plan change?

Questioner

The noise level on my exterior facade is 50.1 dB (including 5 dB deduction). Due to a zoning plan change, this is increased by 1.4 dB. The 5 dB deduction cannot be applied to the internal value. Assuming the facade provides 20 dB of insulation, the interior of the house is 36.5 dB (35 dB is permitted). Question 1: Is the municipality required to install sound insulation? Question 2: What about homes that already have a sound level of 59 dB (excluding the 5 dB deduction)?

Questioner

Is the zoning plan amendment already irrevocable? If not, it's best to appeal the zoning plan, because exceeding the noise limits means the requirement for 'good spatial planning' is not met. The municipality is not automatically obliged to resolve a noise problem; this requires more than just the observation that a certain noise level on the facade or a certain internal value is not (or no longer) achieved. If the noise pollution is caused by a business, it makes more sense to make agreements with the operator regarding reimbursement for insulation measures. If the noise pollution is caused by a road, the municipality would be the point of contact. The fact is that exceeding the statutory noise pollution regulations constitutes an unlawful act. The person responsible for such violations should, in principle, pay the insulation costs.