A woman in California has constructed a network of fire-proof bunkers following devastating wildfires, with British engineering firms emerging as key suppliers of disaster-resistant housing technology.
The bunkers, built by retired architect Margaret Collins on her property in Sonoma County, are designed to withstand extreme temperatures and provide shelter for families and livestock during wildfire events. Collins, who lost her home in the 2020 LNU Lightning Complex fires, spent two years developing the structures using materials supplied by UK-based companies.
The bunkers incorporate ventilation systems developed by Bristol firm AirSafe Technologies and fire-resistant panels manufactured by Sheffield Steel Innovations. These components have been certified to withstand temperatures up to 1,200 degrees Celsius for sustained periods.
UK engineering expertise in disaster-resistant housing has grown significantly over the past decade. The sector now contributes an estimated £2.3 billion annually to the British economy, driven by increasing global demand for climate-resilient infrastructure. Companies such as Resilient Structures Ltd and ThermoShield UK have reported a 40% increase in international orders since 2022.
Collins’ bunkers have attracted attention from local authorities and international disaster management agencies. The structures, which cost approximately $150,000 each, include air filtration systems, emergency power generators and food storage facilities capable of sustaining four people for up to three weeks.
Wildfire seasons have become more intense and prolonged in recent years, driven by climate change. In California alone, over 9,000 wildfires burned more than 2.5 million acres in 2023. The state has experienced six of its largest fires on record since 2020.
The bunkers represent a shift from evacuation-based approaches towards defensive infrastructure. Paul Davies, a structural engineer at Resilient Structures Ltd, described the technology as a logical progression. “We have seen similar adaptations in tornado-prone regions of the United States and cyclone-affected areas of Southeast Asia,” he said. “Wildfires present a unique challenge due to the speed of spread and intensity of heat, but our materials and designs have addressed these variables.”
The British government has invested £15 million in research and development for disaster-resistant housing since 2021, according to the Department for Levelling Up, Housing and Communities. This funding has supported collaborations between universities and engineering firms.
The adoption of fire-proof bunkers raises questions about land use and planning regulations. In California, building codes have been updated to require fire-resistant materials in new constructions, but underground bunkers remain largely unregulated. Local authorities are now reviewing guidelines for such structures.
Environmentalists have expressed concerns that bunkers could encourage development in fire-prone areas. “We need to address the root causes of wildfires and reconsider where we build,” said Dr Helena Ruiz, a researcher at the University of California, Berkeley, who specialises in wildfire ecology. “Bunkers may protect individuals, but they do not solve the broader problem.”
Collins defended her decision. “I am not encouraging anyone to build in harm’s way,” she said. “But for those of us already living in these areas, we need practical solutions. My bunker is not a permanent residence, it is a survival tool.”
The UK’s role in supplying these technologies underscores the country’s post-Brexit strategy of leveraging engineering expertise into specialised export markets. Trade figures show that exports of disaster-resistant building materials increased by 18% in the last financial year, with major markets including the United States, Australia and Japan.
