Why Do I Need A Vacuum Breaker?

Vacuum Breaker 2022

If you’re selling a house in Minneapolis, get some vacuum breakers. When you have a place for a garden hose to connect to the municipal water supply, you need some type of backflow prevention, and that’s what these devices are for. This is one of the required repair items for the Minneapolis Truth-in-Housing evaluation, which is a required inspection for anyone listing a home for sale in Minneapolis.

So why do I need this thing? A vacuum breaker, commonly referred to as a backflow preventer, is a device that prevents the potable water in your home, and possibly your neighborhood, from getting contaminated. It’s basically a one-way valve.

How could your water get contaminated? Picture this scenario: I want to mix up some vegetation killer, so I buy the concentrated stuff, pour it into a garden sprayer, then put my garden hose in the bucket to fill it. I turn the water on, but I get sidetracked with a plumbing project.  I shut off the water to my house, and then open up the laundry faucet to drain the water out of the pipes. This will create a siphoning effect, which could actually suck the nasty chemicals in the garden sprayer back into my home, contaminating the potable water. An even worse scenario would be the city doing work on the water pipes, and the chemical gets siphoned back into the city’s water supply, contaminating a whole neighborhood.

While these scenarios aren’t likely, it has happened many times throughout the country, and the cost of fixing a contaminated water supply for a city is huge. The cost of a vacuum breaker is very little, about eight dollars. While Minneapolis enforces this plumbing code requirement at the time of sale, this isn’t a special requirement for Minneapolis. Vacuum breakers are still required by national plumbing codes all over the country, and they’re required throughout Minnesota by the Minnesota State Plumbing Code, section 4715.2100 (D).

The two most common places where these are installed are at outside faucets and at laundry sink faucets with garden hose threads. An external vacuum breaker is required at outside faucets if they don’t already have one built in. How do you know the difference? Look for the number “1019” or “1011” somewhere on your faucet. If it has that, you don’t need an external vacuum breaker. Check out the examples below; none of these faucets need an external vacuum breaker.

1019A Faucet

1019-C Faucet

1011 Faucet

1011 Faucet 2

If you have a laundry faucet without garden hose threads, you don’t need one of these devices. And you also don’t need them at the water supply connections for your washing machine.

Where can I find a vacuum breaker? Vacuum breakers are sold at hardware stores and big box home improvement stores. You’ll typically find them near the outside faucets. The cheap one pictured at the beginning of this post doesn’t technically meet current plumbing code requirements because it’s not field-testable, but Minneapolis will let them slide.

Written By

Reuben is a second-generation home inspector with a passion for his work. He grew up remodeling homes and learning about carpentry since he was old enough to hold a hammer. Reuben grew up thinking he was going to be a school teacher because he enjoyed teaching others so much. In a sense, that’s a lot of what home inspections are about, so Reuben truly does what he loves. Sharlene has worked with Structure Tech since 2000 and Reuben has been contributing to her blog since 2008.

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