Drip the Faucets: Meaning, Origin & Winter Safety Guide
Quick Definition (Home, Driving & Survival Rules)
A proven home freeze-prevention rule: leaving faucets served by exposed or exterior-wall pipes open at a steady pencil-lead trickle overnight so moving water and pressure relief prevent the pipe from bursting.
Also called: dripping faucets, faucet trickle, let faucets drip
If you only do three things
- Drip BOTH hot and cold lines (or set a single-handle mixer to warm) on exterior walls.
- Open the under-sink cabinet doors so warm room air circulates around the supply pipes.
- Verify the sink stopper is open so the trickle drains freely overnight.
Origin, meteorology & what "Drip the Faucets" means
Plumbers and municipal water utilities have taught 'drip your faucets' for over a century, yet many homeowners misunderstand WHY it works.
While moving water does slow ice crystal formation slightly, the primary reason dripping a faucet stops a pipe from bursting is hydraulic pressure relief: if an ice plug starts to form inside the line, an open faucet downstream gives trapped liquid water an escape route instead of building 2,000+ PSI of pressure that splits the copper or PEX wall.
Real-world winter safety & what to do
When overnight lows drop to 28°F (-2°C) or below in a Southern/crawlspace home (or below 15°F in a northern home with exterior-wall plumbing), open both the HOT and COLD handles slightly to a slow trickle (about 5–10 drops per minute or a thin pencil-lead thread) on the faucet farthest from your main water shutoff.
Always check that the sink drain is completely clear before going to bed so a dripping tap cannot overflow.
Interactive Pipe Freeze Risk & Drip Calculator
Frequently asked questions about Drip the Faucets
Does dripping faucets waste a lot of money on my water bill?
No. A slow drip uses roughly 1 to 3 gallons overnight — costing less than 5 cents of water to prevent a $5,000 to $15,000 burst-pipe flood.
Which faucets in my house need to drip?
Focus on kitchen and bathroom sinks located against outside walls, above unheated crawlspaces or garages, and the faucet farthest from where your main water line enters the house.
Related situational guides
- Preventing Frozen Pipes Step-by-Step: Complete instructions on dripping faucets and insulating pipes.
- Home & Frozen Pipes Overview: Interactive pipe freeze risk calculator.