Insulate exposed supply lines, close crawlspace vents for the length of the freeze, find and test your main shut-off, fit frost-proof hose bibs, and let the fixtures furthest from the meter drip on the coldest nights. If a pipe has already frozen, shut the main before it thaws and warm the run gently - never with a flame.
Before the cold snap
Five things that actually reduce the risk, in rough order of how much difference they make.
- 1
Insulate exposed runs
Foam sleeves on supply lines in the crawlspace, garage and any exterior wall cavity you can reach. Inexpensive, and the job takes an afternoon.
- 2
Close crawlspace vents
For the duration of the cold only - reopen them afterwards so the space can dry out.
- 3
Find your main shut-off now
Crawlspace, garage, or near the meter at the street. Confirm it actually turns. Discovering a seized valve at 2 a.m. is the worst possible time.
- 4
Fit frost-proof hose bibs
A permanent fix to a recurring problem if yours are the old straight-through type.
- 5
Drip the far fixtures
On the coldest nights, on the fixtures furthest from the meter. A moving trickle is far harder to freeze.
What fails, and where
When the east wind comes down the Gorge and the temperature drops below freezing, these are the four places we get called to.
Uninsulated supply runs
Portland has a lot of houses on crawlspaces with supply lines running through unheated air. These freeze first and are the most common single cause of a winter burst.
Pipes in the wall cavity
Older homes often have a run of pipe in an exterior wall with little or no insulation behind it. There is no warning before it goes.
The line to the laundry
An attached but unheated garage holds cold overnight, and the laundry supply crossing it is a frequent casualty.
Hose bibs left connected
A hose left attached traps water in the bib over the freeze. This is the single most preventable failure on the list.
If it has already frozen
Shut the main valve first. A frozen pipe that has split will not leak until it thaws, and the moment it does you want the water already off. Open a tap downstream so there is somewhere for pressure to go as the ice releases.
Warm the run gently with a hair dryer or a space heater kept well clear of anything flammable.
Never use a torch or an open flame. That is how a frozen pipe becomes a house fire, and it is not a hypothetical.
If it has already split, call. Burst pipe repair is dispatched ahead of scheduled work at any hour, and there is no overnight or holiday premium on the rate.
Split a pipe?Shut the main, then call. A live dispatcher answers any hour.
(971) 386-1515