Damage from an Explosion Within a Dwelling
An explosion generates sudden, excessive air pressures. Excessive air pressures produce a wave of air that moves outward in all directions (radially) away from the origin of the explosion. The pressure from the wave of air decreases in magnitude as the distance from the explosion increases. This air wave action is similar to the water wave action generated by dropping a stone into a pond of calm waters.
When the wave of air inside a dwelling encounters an object, such as, a wall, floor or roof, it pushes outward, downward, and/or upward. This outward, downward, and/or upward action is similar to the sudden filling of a balloon with air.
Some damages from an explosion are open and obvious and are considered major damage. Here are a few photographs of some.