Your house will typically retain enough heat to keep water pipes from freezing for about two days after losing power and heat. Conserve the heat inside your house by keeping doors and windows closed and running only properly vented gas fireplaces and gas logs. DO NOT USE cooking appliances to heat! Use your gas cook top, gas stove or gas oven only for cooking. These cooking appliances produce a poisonous gas called carbon monoxide and therefore are to be used only for cooking and heating water.
After the temperature drops below about 40 degrees F in your house, it is time to prepare for the coming freeze and winterize your house. This involves draining the water pipes, as best you can, and protecting sinks, traps and toilets from freeze damage. First – Turn the water supply to your house OFF where the water comes into your house from the street, usually in the basement or utility room in your house. Important – Put a large note to yourself that the water is off and the faucets are open throughout the house which can help you remember to close the faucets and safely restore water flow after a freeze.
Second – Turn ON all the faucets and shower & tub faucets in the house in an attempt to drain all the water out of the pipes. The pipes are freeze-protected if they are empty of water during a freeze. The water will slowly drain out from the lowest faucets which will likely be in your basement near a laundry washer-dryer area or into the bathtub in a slab house without a basement. Leave these faucets open to drain while the water is OFF in your house. Some water will stay in these pipes and may freeze and split … but this is the best chance to minimize potential plumbing damage.
Third – Remove the hoses to your clothes washing machine and open these faucets too.
Fourth – Flush all your toilets at least twice to drain as much water out of them as possible. Minimize the water that is left inside the toilet bowl and the water tank.
Fifth – Pour RV anti-freeze into all areas that may have water in them. Pour RV (Recreational Vehicle) anti-freeze into the toilet bowl, toilet water tank, all sink drains, floor drains, laundry box drains etc. Use only RV anti-freeze and DO NOT USE automotive anti-freeze because it is a biological poison and contaminate which kills the bacteria in septic tank and sewer treatment systems. I suggest you leave the water heater alone during a short term freeze unless you know how to drain & refill a water heater tank. There is a risk of freeze-damaging the hot water tank but the risk is relatively low.
Turning the Water Back ON: When the heat is restored to your house it is time to restore the water service. Go through the house and turn all faucets, showers and tubs to OFF, reconnect the clothes washing machine hoses to the correct faucets, and then turn the water back ON to the house at the main water valve from the street. Water will immediately begin flowing to refill the toilets BUT BEWARE – this is the time any freeze damaged pipes will begin to leak water and cause damage so listen carefully through out the house for flowing water sounds after the toilet tanks are refilled. The water flow sounds should stop after about 60 seconds and be silent while the faucets are still turned OFF. If the water flow sound persists after 60 seconds, shut the water back OFF and look thoroughly through your house for visual signs of water leaks and water damage. If water damage occurs, phone for professional help to locate and repair frozen water pipes.