Fire Safety for Non-conventional Housing

A couple recently died by fire in a “storage-type building being used as living quarters.” I was trying to find the story and found story after story of fires in non-conventional housing, many resulting in serious injuries or fatalities.

The coroner said although the storage-type building was being used as living quarters, it did not have proper electrical connections and was being powered by an extension cord serviced by a home next door.

Fowler added, “A kerosene heater was located inside the structure and is believed to have contributed to the fatal fire.”

WYFF News 4 Greenville, SC

What causes fires in sheds or campers converted to homes?

Many of the fires reported in non-conventional housing that made the news had the same details, powered by an extension cord and heated by a kerosene heater or some other potentially risky heat source.

Extension Cords

Shed conversions are often powered by an extension cord plugged into a nearby house.  An extension cord runs to an exterior house outlet or is even run in through a window to an interior outlet. Everything in the house/shed or camper is plugged into the same cord, overloading it.

Even a heavy-duty 10 or 12-gauge extension cord will get hot if it is overloaded. Often the cord is run under furniture or rugs, increasing the risk of overheating and fire. Even when there are outlets, frequently the outlets are all powered by a single extension cord.

Older or homemade campers are also often just plugged into a nearby outlet. Most newer RVs have 30-amp or 50-amp systems with breakers that cut power to prevent overloading, integrated surge protectors, Ground Monitor Interrupters (GMI), and robust, properly rated wiring. Older campers and DIY campers are not likely to have these safety systems.

Heat or Cooking

Tiny Houses, RVs or campers, or shed cabins are usually quite small with limited or no ventilation. Fumes from kerosene heaters, space heaters or makeshift stoves can build up quickly.

It can be a challenge to keep a heater far enough away from everything in a small space. If your entire living space is only 8’x8’, how are you expected to keep a 3-foot clearance on all sides from a heater?

Space heaters are responsible for 43% of home heating fires, with small rooms making it harder to keep flammable materials (curtains, beds, clothes) at the required 3-foot, 360-degree clearance.

Why are shed-to-cabin or RV fires so deadly?

• No smoke or carbon monoxide alarms
  In many cases the fire was survivable, but the camper or converted shed had no smoke or carbon monoxide detectors.
• Entrapment
  There was no safe way to get out. There was only one door. There were no windows or they were too small to get out of.
• Flammable Construction
  A wood framed shed can be fully engulfed in 5 to 10 minutes. Average fire department response time is 6-8 minutes. Plywood or OSB siding can burn faster than you would even believe since they are often made with combustible adhesives.
  The newer an RV is, the more likely it is to be built with fire resistant materials less likely to ignite or smoke.

Some tiny house are built to a higher standard than sheds, but they may rely on self-certification instead of inspection.

Residential building code requires materials and safety measures that lower fire risk. They are inspected to ensure they are lower risk.

Sheds, even sheds built to code, are built to Risk Category I. They are meant to be storage, not habitable space. Residential buildings are required to have one-hour fire-rated walls, usually drywall. Code calls for fire-resistant materials like fiber cement siding or metal in high-risk areas. Most sheds are made of easily combustible materials that may be highly flammable.

Residential building code require permits and inspections for electrical work. DIY wiring or overloaded extension cords present a risk.

Newer RVs are safer, but not safe like a home built to residential fire code. RVs, especially old campers, don’t meet these safety measures. They are legally classified as vehicles, not permanent dwellings. Campers and RVs use lightweight, often combustible materials (like thin plywood and plastics) that allow fire to spread much faster than in a traditional home built with fire-rated drywall and masonry. They prioritize mobility and lightweight construction over permanence and fire-resistance. They are likely to have less advanced electrical systems, too.

The highest risk of fatal residential fires is smoking. But next come heating, cooking and unattended candles and other flames.

Heaters are a leading cause of home fires, particularly during winter months. According to the National Fire Protection Association (NFPA), space heaters account for about one-third of home heating fires and over 80% of home heating fire deaths.

The most common cause (54% of fatal heating fires) is placing heaters too close to flammable items like bedding, curtains, or furniture.

Plugging high-wattage heaters into power strips or extension cords often leads to overheating and ignition.

Kerosene, natural gas, propane, and wood heaters can release dangerous fumes, particularly carbon monoxide (CO), which is an odorless, colorless, and potentially lethal gas produced by any heater that burns fuel. Using an unvented heater in a small space is extremely dangerous.

So what heat is safer to use? I’m doing the research now.

Featured photo is not real. It is made from a photo by Jess Mann.