The drying time for water-based paint on walls and ceilings can vary depending on several factors, such as the specific brand and type of paint, environmental conditions, thickness of the paint layer, and ventilation in the room. As a general guideline, water-based paint typically dries to the touch within 1-2 hours.
However, it's important to note that drying to the touch does not mean the paint is fully cured. It's advisable to wait for at least 24 hours before applying a second coat or before allowing any contact with the painted surface to avoid smudging or damaging the paint.
Keep in mind that humidity levels, temperature, and airflow in the room can affect the drying time. High humidity and lack of ventilation can prolong drying times, while low humidity and good airflow can expedite the process. If you're painting in a humid environment, consider using fans or dehumidifiers to help speed up the drying process.
Always refer to the specific instructions provided by the paint manufacturer, as they may have recommended drying times and additional guidelines for optimal results.