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PLUMBING SYSTEM INSPECT DIAGNOSE REPAIR
ANTIFREEZE for BOILERS
BACKUP PREVENTION, SEWER LINE
BLOCKED DRAIN REPAIR METHODS
CLEANOUTS, PLUMBING DRAIN
CLOGGED DRAIN DIAGNOSIS & REPAIR
FREEZE-PROOF A BUILDING
FROST HEAVES, FOUNDATION, SLAB
HEAT TAPE USAGE GUIDE
HOT WATER HEATERS
INSULATION INSPECTION & IMPROVEMENT
NO HEAT - BOILER
NO HEAT - FURNACE
ODORS & SMELLS DIAGNOSIS & CURE
OIL FIRED WATER HEATERS
PIPING IN buildings, Clogs Leaks Types
PLUMBING FIXTURES, KITCHEN, BATH
PUMPS, PONY PUMPS
RELIEF VALVE LEAKS
SEPTIC SYSTEM INSPECT DIAGNOSE REPAIR
SHUTOFF VALVE LOCATION, USE
SUMP PUMPS GUIDE
TRAPS on PLUMBING FIXTURES
WATER HEATER PROBLEM DIAGNOSIS
WATER HEATER PROPERTIES
WATER, WELLS, WATER TANKS: TESTING GUIDE
WATER SHUTOFF VALVE LOCATION, USE
WATER SHUTOFF VALVE, WELL PUMP
WATER SOFTENERS & CONDITIONERS
WATER SUPPLY & DRAIN PIPING
WELLS CISTERNS & SPRINGS
WINTERIZE A BUILDING
Freeze-protection for buildings: this article explains where, why, and how to add heat at cold problem spots to avoid freezing pipes. We discuss the safe use of heat tapes in buildings and warn about unsafe heating tapes and fire hazards. 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. We discuss various methods to give each spot in danger of freezing its own heat source. For example simple passive heating may be sufficient to avoid freezing in some locations: in kitchens and bathrooms we may leave open vanity cabinet doors to permit warmer building air to reach pipes in those areas.
Green links show where you are. © Copyright 2013 InspectAPedia.com, All Rights Reserved. Author Daniel Friedman.
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.
Other Common Locations for Heating Cables or Tapes to Prevent Pipe Freeze Damage
Common locations where heating tapes are used on plumbing to prevent freezing pipes include:
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.
Advice For & Warnings About Using GFCI-protected Circuits to Power Heat Tapes to Avoid Fires
Watch out: some models of heat tapes used for freeze protection can cause a building fire if the tapes are not installed according to the manufacturer's recommendations, particularly if the tape crosses over itself.
As Ryan Duffy points out, connecting the heat tape to a GFCI-protected circuit can substantially reduce the risk of heat tape fires. However if the GFCI-protected heat tape circuit trips-off during typical current leakage conditions and without drawing attention of the building occupants, the risk of freeze damaged piping, leaks, water damage, and mold damage will be increased.
The US CPSC recommended in 1994 that HUD consider dropping its no-GFCI-on-Heat-Tape-Circuit provision, and that heat tape powering electrical circuits be be protected with a GFCI device in the electrical panel rather than at the electrical receptacle or "outlet". Ground fault protection was first required in the 1987 NEC for heat tapes that did not have a metal covering. In 1996/1999 the NEC expanded the requirements for GFCI protection and specified that mobile homes would have at least one heat tape receptacle. [A significant number of heat tape-related fires occurred in mobile and manufactured homes.] Also see AFCIs ARC FAULT CIRCUIT INTERRUPTERS
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.
Watch out: even when freeze-tolerant piping is used, the piping connections, elbows, unions, couplings, and plumbing fixtures are still at risk of frost damage.
See FREEZE-PROOF A BUILDING where we describe GFCI protection on heat tape circuits powering heat tapes for manufactured and mobile homes. Similar issues regarding building water entry control are discussed at Sump Pump Inspection. Also see Testing Receptacles GFCIs AFCIs. AFCI's are discussed at AFCIs ARC FAULT CIRCUIT INTERRUPTERS. Readers should also see HEAT TAPES & CABLES on Roofs for Ice Dams where we describe outdoor use of heating tapes and de-icing cables to prevent ice dam leaks into buildings.
Frequently Asked Questions (FAQs) about where & how to add heat to freeze-proof water pipes in a house
Question: what about using heat tape on sewer pipes - our mobile home sewer line keeps freezing
You don't say anything regarding using heat tape on sewer pipes. We have an annual problem with a mobile home sewer line freezing. The line connects a toilet, shower and tub so when it freezes it is a mess. - Anon. 9/19/11
Anon, you can add a heat tape on a sewer line provided the tape you choose is connected and secured to the sewer line the way the manufacturer instructs. Make sure that the bottom of the waste pipe is in contact with the heat tape, and provided the heat tape manufacturer permits, insulate the line as well. The combination of a proper heat tape and sewer line insulation is usually enough to stop freeze-up but here are some additional tips for mobile home waste line freeze problems:
Question: what kind of heating tapes can be used on PVC plumbing drains?
I have a PVC drain line for my water softener that goes outside. When it got very cold two winters ago, the drain line froze and it backed up into house. The drain line lays on the ground. I went to a local store to look for heat tape and they specifically stated not to use on drain lines. Is there some type of tape I could use that would be safe, and how should it be installed? - Don Corbett 9/30/11
A concern with heat tapes on plastic piping is that it may damage the pipes. And if your water softener drain is simply draining onto the ground surface, that is an improper and illegal disposition of wastewater in just about every jurisdiction. Unfortunately the proper fix is costly: reroute drainage to a drywell or other approved drainage destination.
If you use drain piping of sufficient diameter and proper slope, even exposed to cold temperatures the drainage will generally not freeze up in normal use. More help on avoiding freezing piping is at WINTERIZE A BUILDING.
Heating tapes and cables can be installed on PVC supply and drain piping provided you choose the right kind of heating tape or cable and that you follow the manufacturer's instructions. Details are in the article above at How to install a heat tape.
Question: is it OK for the water line to run atop a concrete slab or should it be under ground?
In a mobile home in N.E. should the water supply line be placed on top of the concrete slap for 30 feet or more. Would that be up to code? Should the line from the street be 4 feet under ground to within 6 feet of the hot water heater? - Lee Broad 1/23/12
Lee, if you are describing a water line atop the rat slab beneath a mobile home, there are a couple of hazards including freezing and also movement-caused abrasion and leakage. If the line is supported off of the slab by blocks and insulated you may be OK, else you'll need to add frost protection as well. Heating cables (see advice above in this article) are readily available in lengths up to 60 ft. so you won't have trouble finding one long enough. Don't buy one longer than you need and be sure it is connected according to the manufacturer's instructions.
Question: what is the best way to heat a well pit?
what is the best way to heat a well pit - Jim, 10/18/2012
A well pit is intended to protect its contents, well head, piping, possibly even a water tank and pump from freezing by its depth below ground. If you have to add heat then the pit was perhaps not properly constructed, not deep enough, or left uncovered.
That griping done, you could consider adding a small electric heater; We have also used a simple light bulb in a small, closed well pit. The risk of course is that electricity fails or the bulb burns out. That's why I think a small oil-filled electric heater is probably more safe. Be sure that ALL electrical components in a well pit are protected from water, including the occasional well pit flood. - See more at: http://inspectapedia.com/plumbing/Pipe_Heat_Add_Points.htm#sthash.Nk3hbfK8.dpuf.
Question: tips on how to use a circulating pump to prevent water from freezing
Great suggestions - good article!
Beside insulating pipes from cold weather, or trying to use heat tape, a very effective way of protecting pipes from freezing is to introduce a circulating pump into the water system. By installing a circulation system, the water from the 'hot' side of the system gets sent to the 'cold' water line. This greatly reduces the possibility of water pipes freezing because the water temperature never reaches the critical freezing point.
The best circulation system on the market that I've seen is available at http://avoidfrozenpipes.com/ It is the only circulating pump I've seen that doesn't need electricity to run. It can be installed anywhere in the water system, and save hundreds if not thousands of dollars in home repairs if frozen pipes burst from water expansion.
That's my two cents; I hope it helps! - Vincent 1/21/2013
Thanks so much Vincent. We welcome content critique & suggestions for InspectApedia articles. Working together we are smarter than any individual. - Daniel
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