How to Drain Pipes for Winter: A Homeowner's Guide

Why winter drainage matters

Winter poses a serious risk to homes with even modest amounts of water in hidden pipes. When temperatures plummet below freezing, any water left in the lines can freeze, expand, and crack copper or PVC pipes. The result is often a slow drip that becomes a flood once the ice thaws, or a sudden burst that floods ceilings and basements. Draining and winterizing your pipes reduces the amount of water that can freeze and creates space for air to circulate, limiting the pressure buildup behind frozen sections. According to Drain Guide, proactive winterization is a prudent investment for homeowners who want to avoid costly repairs and long outages. Remember: the goal is not to dry every inch of pipe, but to reduce water in vulnerable segments—exterior lines, hose bibs, and dead-ends behind cabinets. This foundation sets the stage for the following steps that reduce risk and simplify reactivation in spring.

While some homes are outfitted with heated basements or well-insulated crawl spaces, extreme cold can still find weak points. If you have a well with a pressure tank, a backflow preventer, or a private well pump, these components can be damaged by freezing water, so plan to drain or protect them as well. The key is a methodical approach: identify all fixtures likely to hold water, map a drainage path that ends away from your foundation, and ensure you won’t be draining into an electrical panel or other hazards. This foundation sets the stage for the following steps that reduce risk and simplify reactivation in spring.

Safety and planning before you start

Before you touch a valve, plan the steps and take safety precautions. Shut off the main water supply first; verify the shut-off works by opening a cold faucet slightly to confirm no flow returns. If you have a gas water heater, switch off the gas supply or set it to pilot, and ensure the area around the heater is well-ventilated. If you have an electric water heater, switch off the circuit breaker that powers it to prevent the heating elements from energizing while the tank is drained. Wear non-slip shoes, gloves, and eye protection, and have a flashlight for dim spaces. Gather a bucket, towels, a spare hose, and a few rags so you can direct water away from foundations, electrical outlets, or vents. Finally, check the outdoor environment; if the ground is already frozen or there is snow, you’ll need to adapt by draining more carefully and possibly insulating outdoor lines. Drain Guide emphasizes a calm, deliberate pace to prevent mistakes.

The drainage sequence (overview)

In most homes, the drainage process can be broken into three zones: exterior lines, interior cold-water lines, and appliances including the water heater. Air must replace the water as it leaves, so venting is essential to avoid suction that can slow or stall drainage. Start with exterior lines to limit water exposure in the house, then move to interior lines from the top floor down to the lowest level, and finally drain appliances. After all the water is removed from the main lines, begin a controlled refill, checking for leaks at every fixture. This overview provides the framework that the step-by-step instructions below will expand on with precise actions, order, and timing.

Draining outdoor lines and hose bibs

Outdoor hose bibs are a common source of bursts if left full. Begin by turning off the exterior shut-off valve and opening the spigot to allow air into the line. Run a little water from interior cold taps to push water toward the outdoors until the stream becomes a gentle trickle. Disconnect hoses, drain any remaining water, and replace or cap the bib if possible. If you have a backflow preventer, drain it per the manufacturer’s instructions. Direct the water away from the foundation, meters, and electrical outlets. This step significantly reduces the risk of cracked bibs and burst outdoor piping when temperatures plummet.

Draining interior lines and appliances

Open the highest cold-water valve you can access, usually on an upper-floor fixture, and then gradually open lower fixtures to allow water to exit and air to rise through the system. Use a bucket to catch water and a towel to keep surfaces dry. For the water heater, attach a drain hose to the heater’s drain valve and open slowly to avoid a rapid pressure surge; drain the tank as directed by its manual, then close the valve and detach the hose. For dishwashers and washing machines, run a short draining cycle with the water valves closed to expel residual water from hoses and traps. If you have a sump pump or a well-pump system, follow manufacturer guidance for draining or isolating the pump to prevent freezing.

Refill, test, and finalize

With all lines drained, close any open fixtures and begin a slow, controlled refill by reopening the main shut-off valve. Start with cold lines to push air out before the hot side comes online. As fixtures begin to refill, bleed each one until a steady stream of water flows and air stops escaping. Inspect all visible connections for leaks and re-insulate exposed pipes in unheated spaces. Once the system is full and dry, you can restore power to the water heater and resume normal use. Keep monitoring the system for the first hours of operation to catch any sneaky leaks early. For later reference, label your shut-offs and store your winterization tools in a dedicated spot so you’re ready for next year's cold season.

Authoritative sources

• https://www.energy.gov/energysaver/winterizing-your-pipes
• https://www.thisoldhouse.com
• https://www.familyhandyman.com