In February 2021, a winter storm stalled over Texas and brought temperatures well below freezing across most of the state for several days. The electric grid, dependent on generation sources that had not been adequately weatherized for sustained cold, failed under demand that exceeded supply. For several million households, this meant not only no electricity but no heat — in some cases for four or five consecutive nights, with outdoor temperatures in the single digits and teens Fahrenheit.

What followed was a household emergency most of those households had not planned for: subfreezing indoor temperatures, burst water pipes, no running water in many homes, and in too many cases, deaths from hypothermia and from carbon monoxide poisoning when residents tried to heat their homes with improvised sources.

The lessons are not Texas-specific. Any region where homes are not built to retain heat through extended cold events — the American South, parts of the Mid-Atlantic, and elsewhere — faces a version of this vulnerability. Even in cold-climate regions, extended power outages in midwinter create the same basic problem: a house that is losing heat faster than any surviving source can replace it.

The primary lesson: understand how fast your house loses heat

The core thing February 2021 illustrated is that houses vary enormously in how long they stay livable after heat loss begins. A well-insulated home in Minnesota, built for cold, might stay above 50°F for 24 hours or longer in a moderate cold snap. A lightly framed house in Texas, never designed for sustained subfreezing weather, could drop into the 40s within hours.

This is worth knowing in advance, not discovering during an event. The factors that govern it:

  • Insulation in walls, attic, and floor. Homes built in warm climates routinely have minimal wall insulation and uninsulated crawl spaces. Cold air infiltrates; heat exits.
  • Window quality. Single-pane windows are essentially thermal holes. Even low-quality double-pane windows are meaningfully better.
  • Air sealing. Drafts and unblocked penetrations (gaps around pipes and wires, attic hatches, fireplace dampers left open) are often larger contributors to heat loss than insulation quality.
  • Home size and volume. A larger house has more thermal mass and more surface area — it takes longer to cool but also longer to heat back up.

The practical action: on a cold day, walk the house and find the cold spots — floor edges, wall outlets on exterior walls, window frames. Those are the heat-loss points worth addressing before a winter that might include extended outages.

Pipe vulnerability: the damage that outlasted the cold

One of the worst-lasting consequences of the February 2021 event was burst pipes. As indoor temperatures dropped, water in supply pipes — particularly in uninsulated exterior walls, in attics, and in crawl spaces — froze. When a pipe freezes and the ice expands, the pipe splits. The damage doesn’t manifest until temperatures rise and the ice thaws: water flows freely into walls, ceilings, and flooring.

Texas saw this at enormous scale because so many homes lacked pipe insulation in areas that never historically needed it. But burst pipes are a risk in any home where pipes run through cold spaces — and in a multi-day outage in winter, that can include a home in a cold-weather state if the heating system fails entirely.

Pipe protection measures that apply anywhere cold is possible:

Know where your main shutoff is. When a pipe bursts, the first action is to cut the water supply. Every adult in the household should know where the main shutoff valve is and how to operate it — not in theory, but by having found it and touched it. Many homeowners do not know where it is.

Insulate pipes in unheated spaces. Foam pipe insulation is inexpensive and installable without professional help. Priority locations: pipes in exterior walls, under sinks on exterior walls, in uninsulated crawl spaces, in attics. Heat tape (thermostatically controlled pipe heating cable) is the higher-reliability option for severe exposures.

During an extended cold outage: let faucets on exterior walls drip slowly (moving water resists freezing); keep cabinet doors under sinks open to expose pipes to interior air; maintain at least 55°F inside if any heat source remains — this is the widely recommended minimum for pipe protection.

If heat is lost entirely: if the interior temperature will drop below freezing for more than a few hours, draining the supply lines is the best protection. This is done by shutting off the main, opening the lowest faucet in the house, and opening all other faucets to allow air in so water drains. Most households will not need this knowledge, but those in cold climates who experience complete heating failure might.

The alternative-heat problem: carbon monoxide deaths

The February 2021 event also produced deaths from carbon monoxide — people who ran generators, charcoal grills, or gas camp stoves inside their homes trying to stay warm. This is a predictable pattern in every major extended power outage: after a day or two of cold, the temptation to use combustion sources indoors becomes strong, and the consequences can be fatal.

CDC guidance on carbon monoxide is unambiguous: never run a generator, gas-powered tool, charcoal grill, camp stove, or any open-flame heating device inside a home, garage, basement, or enclosed porch. Carbon monoxide is odorless and colorless; by the time symptoms present, incapacitation may prevent escape.

Every home should have at least one CO alarm — ideally battery-backed or battery-only so it functions during power outages. CO alarms should be installed on every floor of the home and outside sleeping areas.

The safe alternative-heat options during power outages are limited. Electric space heaters don’t work when the grid is down. The options that do:

  • Propane heaters rated for indoor use. Specific models — Mr. Heater Buddy type, as one example — are designed and tested for indoor use with ventilation. Follow manufacturer guidance exactly.
  • Wood-burning fireplaces and wood stoves. These are legitimate emergency heat sources if the home has them, properly maintained and with proper fuel. Pellet stoves require electricity to run their feed and fan, so verify the model’s backup capability before relying on it.
  • Layering and passive cold mitigation. For milder temperature drops: concentrate people in one small room, use sleeping bags rated for the temperature, hang blankets over doorways to reduce the volume to heat. This is not a solution for multi-day subfreezing temperatures, but it extends the window.

What the planning layer looks like

A household in any region that could experience extended winter power outage — which, after February 2021, should include any warm-climate state — needs a cold-weather contingency branch in its emergency plan:

  1. At what indoor temperature do you leave? Know in advance. Many emergency managers suggest considering departure if the interior drops below 40°F with no recovery in sight — earlier for households with infants, elderly members, or those with medical vulnerabilities.
  2. Where would you go? A friend or relative in the same region may have the same problem. Know a destination outside the affected area.
  3. What heat sources do you have, and are they safe? Inventory them now, not at 2 a.m. on day three of an outage.
  4. Is your CO alarm functional and battery-backed? Test it now.

The February 2021 event was unusual in scale and in the specific circumstances of grid failure. But the household-level vulnerability it exposed — not knowing how fast the house loses heat, not having pipe-protection knowledge, not having a cold-weather departure threshold — is not unusual at all. It is simply the set of things that don’t get tested until an extreme event, and that benefit enormously from a quiet afternoon’s consideration before that event arrives.

FAQ

How cold does a house have to get before pipes burst?

Pipes are at risk when they drop to 32°F (0°C) or below, which typically happens in uninsulated exterior walls, crawl spaces, and attics before interior temperatures reach freezing. The American Red Cross guidance is to take pipe-protection steps — dripping faucets, open cabinet doors — when temperatures outside drop below 20°F (-7°C), particularly if the heating system is marginal or has failed.

What’s the minimum indoor temperature to maintain to protect pipes?

55°F (13°C) is widely cited as the practical minimum. This keeps pipes in interior walls safe; pipes in uninsulated exterior walls, crawl spaces, or attics may need insulation or heat tape to stay protected even with interior temperatures above this threshold.

Can I run a generator in the garage with the door open?

No. The CDC and CPSC are explicit: generators must be operated outdoors, well away from windows, doors, and vents, with exhaust pointed away from the house — never in a garage, even with the door fully open. Carbon monoxide moves indoors rapidly through attached garages.

How do I know if my home is poorly insulated for cold?

Signs: floors and walls feel cold to the touch near exterior surfaces; you can feel air movement near electrical outlets on exterior walls; windows fog or ice on the inside; the heating system runs nearly continuously in moderate cold. An energy audit — available in many states through utility programs — will give you quantified air leakage and insulation data.