How to Prevent Frozen Pipes in San Antonio Before a Hard Freeze
Before a San Antonio freeze: insulate exposed pipes, seal cold-air gaps, cover outdoor faucets and find your main shutoff in case a pipe freezes.
Quick answer
Insulate pipes in attics, garages and exterior walls, seal gaps where cold air reaches them, disconnect hoses and cover outdoor faucets, and open sink cabinet doors during an extended freeze. Learn where your main shutoff is before you need it. SAWS lists a slow drip as one step during long freezes, but no step guarantees a pipe won't freeze.
Article Topics
Hard freezes are not common in San Antonio, which is exactly why pipes in garages, attics and exterior walls are often left unprotected. A few steps before a freeze lower the risk. None of them guarantees a pipe will not freeze.
Insulate Exposed Pipes
SAWS recommends covering exposed pipes with foam or fiberglass insulation sleeves, the thicker the better. Focus on pipes in attics, crawl spaces, garages and exterior walls, and on the lines feeding outdoor faucets and irrigation. Heat cable can help on very exposed runs; use a listed product and follow its instructions.
Seal Cold-Air Gaps and Protect Outdoor Faucets
SAWS also recommends sealing openings where cold air can reach unprotected pipes, such as around outside faucets. Disconnect and drain garden hoses, cover outdoor faucets, and turn off spray irrigation before a freeze so runoff does not turn into ice.
During an Extended Freeze
If the house is cold or the freeze lasts, SAWS suggests leaving sink cabinet doors open so warmer room air can reach the pipes. It also lists letting faucets drip slowly to keep water moving and notes that the extra water use is billed. A drip can help, but pipes can still freeze.
Know Your Main Water Shutoff
If a pipe bursts, shutting off the water quickly is the most important thing you can do. Find your main shutoff before an emergency: it is often near where the water line enters the house or at the meter box. Turn it off and on once a year to make sure it is not seized. If it does not turn easily or leaks, have it replaced before winter.
If a Pipe Freezes or Bursts
If only a trickle comes out of a faucet during freezing weather, a pipe may be frozen. Never use a torch or open flame to thaw it. Open the faucet and warm the pipe gently with a hair dryer, a heating pad or towels soaked in warm water.
If you cannot find the frozen section, or the pipe has burst, shut off the main water supply and keep clear of water near outlets or the electrical panel. Our guide to leaks near wiring and drywall covers the repair order after water damage.
Frequently asked questions
Which pipes are most likely to freeze in San Antonio?
Pipes in exterior walls, garages, attics, crawl spaces, outdoor faucets and other unheated areas are the most exposed during a hard freeze.
Should I drip my faucets during a freeze?
SAWS lists letting faucets drip slowly as one step during extended freezing temperatures and notes that the extra water is billed. A drip can help keep water moving, but pipes can still freeze, so insulation, sealing cold-air gaps and knowing your shutoff matter more.
What should I do if a pipe freezes or bursts?
If a pipe bursts, shut off the main water supply right away and keep clear of water near outlets or the electrical panel. For a frozen pipe, never use an open flame; open the faucet and warm the pipe gently with a hair dryer or warm towels, or call a licensed plumber.
Sources
- San Antonio Water System, Don't Let Freezing Temperatures Burst Your Pipes!. Retrieved October 4, 2026.
- Ready.gov, Winter Weather. Retrieved October 4, 2026.
Burst pipe or frozen line?
Shut off the main water supply first, then call. C.S.W. Power Solutions performs plumbing repairs, including burst pipe and valve repairs, under Responsible Master Plumber license RMP #46592.
Related service: Plumbing Services
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