How to Prevent Frozen Pipes on the Front Range
Disconnect every garden hose before the first hard freeze, which the National Weather Service puts near October 2 on average in Colorado Springs. Then insulate pipes in crawlspaces, attics and exterior walls, close crawlspace vents for winter, and drain your sprinkler backflow. On nights below about 15 degrees, open sink cabinets on outside walls and leave one faucet at a slow trickle.
The pipe that splits in this city is almost never the one anybody worried about. It is a hose bib on the south wall of a house that felt like spring at four in the afternoon and hit nine degrees by midnight.
When does Colorado Springs actually freeze?
The National Weather Service office in Pueblo keeps the freeze records for the region. For Colorado Springs, the mean date of the first 32 degree freeze is October 2. There is roughly a fifty percent chance of hitting 28 degrees by October 10. The earliest freeze on record came on September 1, 1911, and the latest first freeze waited until October 31, 1963.
Those averages hide the part that breaks plumbing. The Front Range runs enormous daily swings, and an arctic front coming down the east side of the mountains can pull the temperature 50 degrees in a few hours. A house that sailed through three mild weeks gets no warning at all. That is why freeze prep here is a calendar job rather than a reaction to a forecast.
What should you do, and when?
| When | Task | Why it matters |
|---|---|---|
| Late September | Pull every garden hose off every hose bib | A connected hose traps water inside the wall where a frost-free bib is supposed to drain |
| Late September | Blow out or drain the sprinkler system and the backflow preventer | Backflow assemblies sit above ground and crack first |
| Early October | Insulate exposed pipe in crawlspaces, attics and garages | Foam sleeves cost a few dollars a length |
| Early October | Close crawlspace vents for the season | Open vents pour freezing air straight across your supply lines |
| Mid October | Find and label your main shutoff, and test that it turns | The night it matters, you will be in the dark with wet socks |
| Mid October | Seal gaps where pipes pass through the rim joist or an exterior wall | Wind driven cold gets in through holes, faster than it soaks through insulation |
| Any hard freeze | Open cabinet doors under sinks on outside walls | Lets room air reach the pipe |
| Below about 15 degrees | Leave one far faucet at a slow trickle | Moving water resists freezing and relieves pressure |
Why are hose bibs the number one failure?
Because of how a frost-free sillcock works. The valve seat sits eight or ten inches back inside the heated wall, and when you shut the handle the water in the tube between the seat and the spout drains out through the spout. That only happens if there is nothing on the end of it.
Leave a hose attached and that tube stays full. The water in it freezes, expands, and splits the copper inside your wall. You will not see a drop of it until spring, when you open the bib for the first time and water starts running down the inside of the drywall.
So the rule is simple. Hoses off before the first hard freeze, every year, including the splitter and the timer and the quick connect. If you have an older bib with a separate shutoff valve inside the house, close that valve and then open the outside bib to let the line drain.
How should you handle crawlspace vents?
Older housing stock in Manitou Springs and around the Westside puts a lot of plumbing in vented crawlspaces on steep lots, and those vents are the difference between a pipe at 45 degrees and a pipe at 20.
Close them for winter. Rigid foam vent plugs or purpose made covers work fine, and they go in around the first week of October. Open them again in late spring so the space can dry out, because a sealed crawlspace through a wet summer grows its own set of problems.
One exception matters. If a furnace, boiler or water heater draws combustion air from that crawlspace, do not seal it up without talking to whoever services the appliance. Starving a gas appliance of combustion air is a worse outcome than a cold pipe. In that situation, insulate the pipes and the ground instead and leave the air supply alone.
While you are down there, look at what the pipes are wearing. Foam sleeve on the supply lines, and heat tape only on runs that have frozen before, installed to the manufacturer’s instructions and plugged into a proper outlet.
What do you do on the worst night?
When the forecast low gets into the single digits or below, work through this short list before bed.
- Open the cabinet doors under every sink on an exterior wall, including the kitchen.
- Set one faucet at the end of the longest run to a steady trickle, both hot and cold.
- Leave the heat at your normal setting rather than dropping it overnight.
- Open the garage door as little as possible if there is plumbing in there.
- If you are leaving town, set the thermostat no lower than 55 degrees and ask someone to check the house.
If you are going away for more than a few days in deep winter, the safer move is to shut the main off and drain the system down.
What if a pipe is already frozen?
No water at one fixture while the rest of the house runs normally usually means a frozen section rather than a supply problem.
Open that faucet so melting water has somewhere to go. Warm the suspected run with a hair dryer or a space heater kept at a safe distance, working from the fixture back toward the cold end. Never use a torch, a propane heater or anything with an open flame on a pipe inside a wall. House fires from thawing attempts are a real annual event.
If the pipe has already burst, shut the main off first and then call. Photograph everything before any cleanup starts, because most homeowner policies pay to dry out and repair sudden water damage even where they exclude the pipe itself.
When to bring someone in
A split hose bib, a cracked backflow assembly or a supply line that opened up inside a wall all get handled the same day. See our leak detection and repair page for what that visit involves and what it costs. If the water is running right now, shut the main and call the emergency line before you do anything else.