Polish households urged to use night ventilation and shading to keep indoor temps near 20 °C

Guides for Polish homeowners recommend maintaining indoor temperatures around 20 °C by controlling airflow, shading windows, and limiting internal heat sources. Night ventilation for 6–8 hours, then closing and covering windows in the morning, can significantly reduce heat gain. Additional low‑tech measures include hanging a wet sheet on the airflow side for evaporative cooling, using a fan aimed at a bowl of ice, and keeping appliances that generate heat (e.g., ovens, dryers) off during hot periods.

Both articles stress that glass windows transmit solar radiation, so closing blinds or shutters early in the day—especially on south‑ and west‑facing windows—and using reflective or light‑colored coverings can block much of the incoming heat. Reducing internal sources such as electronic devices, lighting, and body heat further prevents rooms from turning into “saunas.” Together, these actions can lower energy consumption for heating or cooling by several percent while keeping comfort levels stable.