What is the minimum footing thickness for Group A dwellings under PD 1096?

The minimum footing thickness for Group A dwellings under the National Building Code of the Philippines, specifically PD 1096, is set at 250 mm. This requirement is designed to ensure the structural stability and integrity of the building. Footings are critical components in distributing the load of a structure to the ground, and having a specific minimum thickness helps to prevent issues such as settling and cracking due to uneven load distribution or inadequate support.

The requirement for 250 mm reflects considerations for various factors, including soil bearing capacity, load transfer from the superstructure to the footing, and overall safety and durability of the building over time. While other thickness options may seem plausible, the regulations set a standard that is both practical and based on engineering principles to promote safety in construction practices for different types of dwellings.