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• How to Find & Fix the Spots where Water Pipes are Likely to Freeze
• How & Where to add heat to protect against pipe freezing: heat tapes, heaters, light bulbs, insulation
  
• How to avoid freezing water supply pipes and drain piping, drains, traps, toilets, etc.
• How to winterize pipes: frost protection for plumbing systems

The articles at this website will answer most questions about freeze protection for piping and other building plumbing and heating system components: how to winterize a building to avoid frozen pipes, and how to thaw frozen water supply & drain piping, wells, & water tanks.ff

Guide to Finding and Correcting Freeze-Up Risk Points in Buildings

You can do a lot to correct a freezing pipe problem in a building that is exposed to cold weather. Even in an occupied building pipes can freeze in some conditions. Here are some examples of places to look for freezing trouble and what to do about them:

Water pipes (both supply & drain) & hot water heating pipes or steam heat condensate pipes or building drains routed through un-heated areas or passing by areas exposed to cold drafts. Check piping that runs along or near the building sills or building perimeter in basements, crawl spaces, attics. Check water supply piping and horizontal drain lines and fixture traps in cold areas where building heat does not easily enter, such as the pipe chase at left. Often you can simply cut an opening to let warm air enter such spots.

• Look for drafts: On a cold, windy day, explore your home, especially the un-heated areas such as where pipes pass along or close to the building perimeter sills or foundation top in basements or crawl spaces. If the building has sections of floor that overhang lower parts of the building (such as a raised ranch) be sure the floor under-side is well-insulated and thoroughly sealed against drafts. When cold wind blows against a home which has an overhanging floor, wind against the building can force cold air into the wall cavity or even up into the building walls through a poorly-sealed under-side of the overhanging floor.
  
  Explore the building on a cold windy day, looking for drafts: feel for cold drafts that blow on water piping or heating piping. Fix those drafts and you'll significantly reduce the chances of a frozen pipe. Fixing a draft means adding caulking, a plastic air barrier, using foam insulation, or other means to block un-wanted air flow into a building.
• Look for places where pipes touch un-heated surfaces, such as foundation surfaces or framing. These may conduct heat away from the pipe and speed freezing at that point.
• Look for the coldest of the un-heated areas where pipes run, such as an un-insulated attic, a pipe chase in a building corner, a crawl space (especially near foundation vents or other drafty spots), or as we explained just above, in a raised-ranch type home, where pipes run in the section of an upper floor which overhangs the building foundation (and may be poorly insulated).

Look for evidence that pipes have frozen before, and find out why the freeze occurred in that spot. You may see a bulged pipe that didn't burst (if it burst it would have leaked and been repaired), or you may see a section of piping with one or even several pipe couplings soldered in place, a likely indicator that that section of piping has frozen before. In our photo at left you can see that freezing has damaged the heating baseboard pipe and a copper pipe coupling has been used to make a repair by replacing a damaged section.

Plumbing fixtures in un-heated areas such as a bathroom or kitchen sink in a room that does not have its own heat source; in kitchens and bathrooms we may leave open vanity cabinet doors to permit warmer building air to reach pipes in those areas.

How & Where to add Heat to Protect Plumbing Pipes or Components from Freezing

Adding heat to protect plumbing in un-heated areas such as crawl spaces: you may add heat either by installing a short section of heating baseboard, an extra opening cut in a warm air supply duct running through a crawl area, a small thermostatically-controlled electric heater set to operate only at low temperatures, or in small but cold areas, a simple light bulb may provide enough heat to prevent freezing.

Check these auxiliary heaters frequently to assure that the heat source is still working; be sure to respect fire safety when installing any heat source. Adding small point-sources of extra heat in a building to protect from freezing is likely to be more economical than running the central heating system to a higher temperature just to warm up a cold corner or two. Particularly if the thermostat set-back temperature results in the heating system turning on less often, adding point source heating may be needed.

We can add heat to protect plumbing and heating piping using any of the methods listed below and described in detail in this article:

• Increase the flow of warm building air from the heated space into the cold corner or spot at risk of freezing by cutting one or more openings that let air circulate into the cold spot. In some bathrooms or kitchens we may simply leave the cabinet doors open to let room air reach sink plumbing.
• Add a point-source of heat such as a tiny low-temperature-on electric heater, a short section of hot water heating baseboard, or by cutting an extra opening to let warm air blow out of a warm air supply duct into the cold area
• Use heat tapes on piping in areas which are difficult to heat
• Use a light bulb as a heat source
• Add insulation on piping to protect it from freezing
• Change heating system controls to continuously circulate the water inside of heating baseboards or radiators even when the boiler is not itself heating the water.
• Leave water faucets open to a drip or very slow trickle: this is an emergency procedure that you may need to use if your building loses heat. Normally it's not a great idea to leave water running as we are wasting water, risking frozen drain lines, and if a septic system is installed, we risk flooding the septic system.

Increase warm air flow: Another way we've added heat to problem areas where pipes freeze is to simply make one or more openings to permit warm air to circulate from the building into the cold area. After finding freezing water pipes entering a bathroom located over a kitchen in a home with warm air heat, we cut an opening in the kitchen ceiling and installed a heating register there to make the hole look nice. Warm air rising from the kitchen proved sufficient to prevent a future freeze-up of the pipes in that location.

In any cold area where you are adding heat to avoid freezing pipes, the amount of heat you need to add will be reduced a lot if the cold area itself is insulated. Fiberglass insulation is fine for most building locations, but to reduce the risk of mold growth, we prefer to use solid foam insulation in areas like crawl spaces that are exposed to dampness.

Guide to Using Heat Tapes to Protect Pipes From Freezing

Common locations where heating tapes are used on plumbing to prevent freezing pipes include:

• Water pipes run through attics
• Water pipes run through un-heated crawl spaces
• Water pipes and equipment in un-heated garages
• Water equipment in well pits
• Water pipes running under porches

Some older or less costly models of heating tapes present a fire risk, particularly if the heating tape is crossed over itself. Be sure to read the product specifications, safety warnings, and installation guide before installing a heating tape on building piping of any kind.

Pipe Heat Tape Safety Guide from the US CPSC

The U.S. CPSC has provided safety recommendations for homeowners using heat tapes to help prevent fires: Replace heat tapes that are older than three years Use only heat tapes certified to meet recognized voluntary fire safety standards such as those provided by Underwriters Laboratories (UL), the Canadian Standards Association (CSA), and the Factory Mutual Research Corporation (FMRC). Plug the grounded (3-prong) plug into a grounded GFCI (ground-fault circuit interrupter) protected electrical outlet Don't cross the heat tape across itself unless the manufacturer says that's acceptable - crossed heat tapes can overheat and start a fire Put the heating tape on the surface of the pipe to be protected from freezing, not on top of pipe insulation, and do not cover the heating tape with insulation unless the manufacturer says that's acceptable. Use only non-combustible insulation on pipes where heating tapes are installed (like fiberglass insulation). Foam or vinyl pipe insulation may catch on fire from a faulty heat tape or faulty heat tape installation. Protect the sealed end-cap of the heat tape (see our photo above) from damage and water leaks which could cause a short circuit or fire. Use heating tape only for the application approved for that particular heating tape, such as for use on piping. Some heat tapes are designed for use in gutters or driveways while others are designed for use on piping or fuel piping. Be sure that the heat tape thermostat (if one is provided) is placed where the instructions say. For example some heat tape thermostats should be placed in contact with the pipe, others left hanging in air. (See our photo above) Replace any heat tape that is discolored (a sign of overheating), cracked, melted, or damaged in any way.

Guide to Pipe Insulation to Prevent Freezing

Plastic piping to resist freezing: modern plastic piping is considerably more tolerant of freezing without bursting than copper or steel water pipes. In a home intended for regular winterization some builders use exclusively plastic pipes to resist freeze damage. Be careful: even when freeze-tolerant piping is used, the piping connections, elbows, unions, couplings, and plumbing fixtures are still at risk of frost damage.

Use links just below or at the left of each page to navigate this document or to view other topics at this website. Green links show where you are in our document or website.

FREEZE-PROOF A BUILDING
Key Winterizing Topics
How to Winterize a Building

Winterize - Heat On Procedure
  Thermostat Settings
  Turn Water Off ?
  Winterize Water Softener & Treatment Equip.
  Find & Fix Water Pipe Freeze-Up Points
  Heat tapes, Heat, Insulation prevent Freeze-Up
  Freeze Protect Drains

Winterize- Heat Off Procedure

De-Winterized a Building
  Thawing Frozen Pipes
  Repairing Burst Leaky Pipes
  Turning on Heating
  Restoring Drains
  Turning on Water
  Water Supply/Drain Pipe Leak Types
  Restoring Water Softener & Treatment Equip

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• Daniel Friedman - principal author/editor of the InspectAPedia^® Website
• Critique, contributions wanted: Contact Us to suggest corrections or additions to articles at this website, and if you wish, to receive online listing and credit as a contributor. Particular thanks are due to the many experts and also consumers who read and critique technical articles at InspectAPedia.com.
• "New Electric Heat Tapes Help Prevent Fires," US Consumer Product Safety Commission (CPSC) #00936
• Thanks to Alan Carson and Bob Dunlop, Carson Dunlop, Associates, Toronto, for permission to use illustrations from their publication, The Illustrated Home which illustrates construction details and building components. Carson Dunlop provides home inspection education, publications, report writing materials, and home inspection services. Alan Carson is a past president of ASHI, the American Society of Home Inspectors.
• "Freezeproof Your House," Mike McClintock, Rodale's New Shelter, p. 30, October 1985 (approximate date)
• "How to Winterize Your Pipes," Mike McClintock, Homeowners How-To Magazine, p. 59-62, Nov-Dec 1979.
• Critique, contributions wanted: Contact Us to suggest text changes and additions and, if you wish, to receive online listing and credit for that contribution.

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