"Understanding Your Home" by Building Inspector Mark Visser
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Hose bibb. Hose bib. Spigot. Sill cock. Anti-syphon sill cock. Anti siphon valve. Backflow preventer

Regular, older type hose bibb. To prevent freeze-up close the inside valve and open the outside valve to drain all water from the tap. Do not close the outside tap during the winter months.

Did you noticed that there is no caulking around the copper supply pipe? This opening should be closed to keep cold air outside and to prevent pipes from freezing inside the house!!
Your regular hose bibb can be fitted with a backflow prevention valve. This anti-siphon adaptor threads onto the end on the hose bibb to protect the water supply from contaminated backflow. This is a practical, economical, and fast way to retrofit an existing hose bibb to comply with the local building codes requiring back-flow prevention.
Preparing for winter:
1. Remove the backflow preventer.
2. Close indoor shut-off valve.
3. Open outdoor valve to drain the water and leave it open till spring.
Hose Bibb
Also known as: Spigot, Sill cock, Faucet, Tap

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Hose bibb. Hose bib. Spigot. Sill cock. Anti-syphon sill cock. Anti siphon valve.
Backflow preventer.

WARNING about lead content.
Most hose bibbs purchased prior to late 1990s were constructed of brass or chrome-plated brass, which contain up to 8 percent lead. Look for faucets that are labeled "Low Lead Compliant".
For more information go to "Lead in Drinking Water"

The device that supplies water to the outside of the house is known by many names. Some of the more common names are: tap, faucet, spigot, sillcock or hose bibb. I will refer to them as hose bibbs though there are many areas where they are only known as spigots or sillcocks.
There are many different type of hose bibbs.
The more common ones for outside use are described below.
- Regular hose bibbs
- Anti-freeze hose bibbs
- Anti-syphon hose bibbs
- Finishes
- More helpful links

Depending on where you live the hose bibb may be known as a spigot or faucet in your area. Sometimes it is written with one one b as in bib but I prefer the double b spelling so, right or wrong, I will refer to it as hose bibb. The hose bibb can be attached to an exterior wall so a garden hose can be hooked up and used for watering the garden and lawn. In my own home I also installed a hose bibb in the garage which comes in handy for washing the car and hosing down the driveway. Typically a hose bibb has a single valve and is turned on and off with a metal wheel handle. Hose bibbs have to be protected from freezing in cold climates. Depending on the type of hose bibb installed there are two ways of doing this, see below.

Anti-freeze / anti-syphon hose bibb. The stem is extended to the inside
where the actual on/off valve is located. With the valve closed there is no
water left in the stem which could freeze up.

If you live in a colder climate, your hose bibb has to be protected from freezing to prevent pipe burst, and as result, water damage to your home.
Regular hose bibb.
If you have a standard hose bibb there should also be an inside shutoff valve in addition to the outside one. To prepare for winter take these steps:
1- Close inside shutoff valve.
2- Open drain cap on inside shutoff valve (if there is one).
3- Open outside hose bibb (and leave it open all winter) to drain water from pipe section going through exterior wall.
Anti-freeze or frost free hose bibb.
This type of hose bibb has a long stem that extends all the way from the outside to the inside of the house where it is connected to the supply line. Though the wheel handle is outside, the actual valve to open and close the hose bibb, is on the (heated) inside of the house. With the valve closed, any water from the valve to the outside is drained and cannot freeze. It is important to install the frost-free hose bibb with a slight slope towards the outside. Anti-freeze hose bibbs are available in lengths from 6" to 14" (15-36 cm) in increments of 2" (5 cm).
Do NOT insulate the hose bibb water supply line inside the house.

Anti-syphon hose bibbs are mandatory in many jurisdictions, including the State of California. To make sure if they are required by code or not, check with your local building department. The picture of an anti-syphon hose bibb, shown to the xxxxxxxxxxxxxxxxxxxxxxxx was taken at a house under construction in Kempville, just south of Ottawa, ON.
An anti-syphon hose bibb has a one-way valve that prevents unsanitary water (from swimming pool, laundry tub, sprinkler system) from being pulled back through a garden hose and contaminating your water system. Click here for more information on cross contamination. The main reason for why this can happen is if the city water pressure were to suddenly drop. One of the reasons for a sudden drop in water pressure could be if there would be a major fire in your neighborhood and several hoses would be hooked up to fire hydrants connected to the same water main that supplies water to your home.
The sudden drop in pressure and volume could literally suck the water out of the plumbing pipes in your house. The top cap of an anti-syphon hose bibb has vent openings to release any water from an attached closed and pressurized garden hose. Beware, stand back so that you don't get sprayed when you turn off the hose bibb!!

As they are located outside they have to be able to withstand the elements. Normally speaking, they do not have the same shiny finishes as taps located inside the house and are usually made of plain brass. If the hose bibb is located inside a garage they can have a chrome finish as shown above.

Faucets - Kitchen, Bathroom
Faucets - Bathtub/shower, shower

Faucets - Warning about air gap and cross contamination
Laundry Tubs, Sinks and Taps
Lead in drinking water from faucets, solder and watermains

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