Cages are for the Birds: Backflow Enclosures Outperform Backflow Cages

In my travels across the country, I have encountered many territories and jurisdictions which only use metal cages to protect their backflow preventers. This should not be a recommended practice for two key reasons: theft protection and freeze protection. These are actually the main two reasons for buying some sort of backflow cover in the first place.


One of the primary purposes of backflow enclosures is to deter and prevent theft. Backflow preventers are manufactured from 3 common metals – bronze, stainless steel and cast iron - all of which are very valuable at the scrap metal yards. When a metal thief passes a backflow preventer in a see-through cage, it simply alerts them to a valuable assetWould the sight of all this copper and bronze on the right deter a metal theft? Here is an excerpt from an article found on the Scottsdale, AZ website which highlights the frequency of valve theft, "Due to the scope and frequency of backflow assembly thefts valleywide, the City of Scottsdale Cross-Connection Control Program would like to offer some suggestions to help prevent this type of property crime." Another example comes from the Denver Post when more than 100 backflow devices were stolen in less than a year, "Police in Aurora are trying to figure out who is stealing backflow preventers - devices used to stop contaminants from entering the city's drinking water system." Here is yet another example, from the city of Surprise, AZ, "Officer Mark Ortega, crime prevention officer for the city of Surprise Police Department, says, "Thefts of backflow valves are commonplace everywhere in the Valley.

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As you can see, backflow preventer theft is wide spread and causes major problems for water jurisdictions across the country. These intances are common, and we frequently see news articles surface on this topic. However, these articles highlight the problem but do not offer good solutions. Putting a protective cage over your backflow does not prevent theft, it only slightly deters it. In fact, in the city of Surprise article, the officer says, It makes no sense to put a $500.00 valve in an expensive cage protected by a $1.50 lock. They also recommend painting the exterior of the valve because painted parts are less valuable at the scrap yard. This is not a good idea, as painting the valve can clog test cocks and prevent check covers from opening, both of which hinder the maintenance process and will nullify the manufacturer’s warranty.

Freeze Protectionbackflow_cages_offer_no_freeze_protection.jpg

Another primary function of a backflow enclosure is to protect the valve from freezing. Most “warm weather” jurisdictions feel that backflow cages are adequate protection because freezing simply does not occur. However, over the past few years, even warm weather climates have experienced major freezing events. Would the valve on the right stay warm in freezing conditions?

2010 - Orlando, FL had a major freeze which damaged thousands of backflow preventers and pressure vacuum breakers, most of which had to be completely replaced.

- Miami, FL temperatures reached 21 degrees and also caused major valve damage, most of which had to be replaced at the owner’s expense.

2011 - El Paso, TX experienced a major freeze event, which resulted in wide-spread replacement of valves in the City of El Paso, as well as over 1200 backflow preventers replaced on the base at Ft. Bliss.

2015 - Phoenix, AZ and Tucson, AZ both experienced a hard freeze event which resulted in frozen and damaged backflow preventers that had to be replaced at the owner’s expense.

As you can see, even traditional sun-belt states and warm weather cities actually have freezing conditions on a regular basis. Metal cages will not protect your backflow preventers and you will have to repair and replace them in the event of freezing temperatures. However, it looks warm and toasty inside the ASSE 1060 approved enclosure below.


Another common misnomer about cages is they cost less than ASSE 1060 approved enclosures. This is simply not true. The use of cages began because of rampant valve theft in AZ, NV and CA.  Backflow cages were perceived as more cost effective than aluminum or fiberglass enclosures and the pop up of multiple cage manufacturers supplied the demand and established the habit of using cages. However, domestic manufacturing efficiencies have made ASSE certified enclosures extremely cost competitive and in many areas are actually cheaper than their see-through cage counterparts.  The next time you install a backflow preventer and need to protect it, please call your local supply house and compare the cost of a see-through cage and an ASSE approved enclosure. You will be pleasantly surprised at the quality you can upgrade to at virtually the same price.

What Benefit Do Cages Have?freeze_protection_from_asse_1060_backflow_enclosure.jpg

Cages are simply not a good solution for the protection of backflow preventers. Instead, consider an aluminum backflow enclosure. What's inside the industrial enclosure on the right? Who knows, and there's no temptation or easy way to find out. The only enclosures that truly protect valves from vandals, thieves and Mother Nature are ASSE 1060 approved enclosures.  The approval guarantees that the enclosure meets industry standards for freeze protection, structural design, drainage performance, testing and maintenance access and security. With all of those qualifications, you are guaranteed that your backflow preventer will continue to protect your water supply, and that is peace of mind that we all can all rely on.

aluminum enclosures


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