The blue house partially damaged in flash floods stands on the banks of the Trishuli river in Nepal's Nuwakot district, Thursday, Sept. 3, 2026. APOn August 26, a flash flood swept through Nepal’s Bagmati province after a massive chunk of the Langtang Lirung glacier sheared off into the Trishuli river valley. The impact launched a wall of water, boulders and sediment down the Trishuli River corridor that swallowed bridges, highways and settlements. More than a thousand people are dead and thousands more are missing.In Nepal’s Nuwakot district, however, a single turquoise-coloured house was photographed standing upright in the middle of a wasteland of thick mud. The residents of the house had sought shelter on the upper balconies — which extended to the fourth storey. No formal engineering audit has been conducted, but the visual evidence does lend some insight into the structural resilience of a house constructed more than 40 years ago. The house in questionThe turquoise house grabbing the attention of the world is located in the Devighat area of central Nepal’s Nuwakot district. The house belongs to Prakash Pandey Pyakurel, a grocer, who resided on the upper levels. Pyakurel and his family were trapped inside for close to two hours during the floods, according to news reports.The family confined themselves to the upper levels which remained intact. The walls of the lower floor, however, were blown out and only the skeletal pillars supporting the building remain, show images. This may have allowed the water to flow through, helping the building stay erect.How the family trapped inside Nepal’s “Blue House” was rescued[ Ganesha Shrestha] pic.twitter.com/nkH57tcFUU— Massimo (@Rainmaker1973) August 30, 2026Why the house did not succumbThe temperatures of the Himalayas mean that settlements prioritise thermal insulation and structures that can carry vertical gravity loads. They are built relatively shallow in the ground. One of the most commonplace issues with floods is the erosion of the topsoil which causes foundations to erode as well. Flash floods also cause soil liquefaction. This is when waterlogged ground loses its strength to stay together and its properties mimic those of a liquid, not a solid. Story continues below this adAccording to reports quoting Pyakurel, the owner of the house, his family anticipated the geographic risks of the Trishuli river. Decades ago, they dug two floors down to lay an over-engineered base using heavy road-grade material and robust steel pillars. The reinforced skeleton, driven deep into the earth, may have helped stabilise the structure.How a building’s compressive strength matters herePyakurel’s Nuwakot house appears to be constructed using a grid of steel-reinforced pillars and beams. This is commonly referred to as a reinforced cement concrete (RCC) structure.Generally, walls are the load bearing component of a building’s structure largely because they transfer the weight to the foundation. An RCC frame is slightly different. The concrete provides compressive strength sufficient to support the building’s weight and the steel rod grid provides the tensile strength that lets the structure bend slightly without snapping.Story continues below this adIn 2015, Nepal was hit by an earthquake responsible for close to 9,000 fatalities. Consequently, building codes across the country promoted a shift towards RCC column-and-beam structures. This was because the earthquake exposed that the majority of homes in Nepal lacked the capability needed to withstand lateral shaking.Pyakurel’s Nuwakot house was designed to withstand such horizontal forces and had the capability to absorb the flood’s energy. Additionally, Pyakurel’s house may have benefited from its location. It was positioned slightly away from the fastest-moving channel of the flood, which may have spared it collisions with the heaviest debris.