The green-painted two-story house in Nuwakot withstands mud and rock floods thanks to its reinforced concrete frame and convenient location.

When flash floods destroyed almost the entire village in Nuwakot district, the blue-painted two-story house remained standing, saving the lives of the family on the balcony.

On August 26, a Himalayan glacier collapsed, pushing large amounts of water, rock, ice and mud into the river system of central Nepal. The flood flow swept through many residential areas, destroying houses, bridges, roads and hydroelectric projects along the way.

In Nuwakot district, a family was trapped in a two-story house painted green. Videos circulating on social networks show them standing close together on the balcony, below is a stream of murky water carrying large rocks, uprooted trees and broken pieces of houses.

The water flowed rapidly on both sides, cutting off all escape routes. People on the balcony could only watch nearby structures collapse and disappear one after another. Their house is still standing.

A few hours later, video taken at the same location showed that the water had receded, mud covered the area but the house did not collapse. Those trapped inside also survived.

The architectural account Architecture Presentation on the X platform said that the reinforced concrete frame is the main reason why the building can withstand water. The system of columns, beams and foundations are connected together with continuous steel, forming a unified block. When the flood current hits the wall, the impact force is transmitted through beams, columns and then down to the foundation instead of being concentrated on a single wall segment.

This hypothesis is similar to studies on damage caused by mud and rock floods. In 2012, a group of scientists from the Chinese Academy of Sciences surveyed eight structures after the flash flood disaster in Zhouqu, Gansu province. Results published in the journal Natural Hazards and Earth System Sciences show that houses with reinforced concrete frames can withstand significantly greater impact forces than brick and concrete houses without equivalent frame systems.

In addition to materials, research at Chu Khuc shows that the level of damage to houses also depends on the speed and depth of the flow, the direction of the house and the shape of the building.

Image analysis shows that the green house in Nepal is located off the main stream and at a higher position than its surroundings. This position helps the house's foundation avoid large rocks that often roll in the deepest and most fast-flowing water areas.

The compact shape of the house also causes water to separate to the sides, minimizing pressure on the facade. The process of mud accumulating around the base of the house during the first floods creates a natural slope, pushing the flood waves behind it around the building.