The most common objection we hear about the use of above-ground enclosures for backflow preventers is the aesthetics. We get it. No one wants another big, shiny box distracting customers from the appearance of a new building. But the best location for the backflow device is above ground in an ASSE 1060 enclosure. Backflow devices should not be installed in a vault for risk of a cross-connection when the vault floods and RPZs shouldn't be installed inside the building where they could potentially cause significant flooding. So what do you do? Let's look a a few considerations including colors, landscaping, location and sizing.
This may seem obvious, but few designers realize enclosures are available in many colors. On many commercial projects, we've noticed the electrical transformer is green and it looks much more aesthetically pleasing. Notice the green enclosures in the picture below. They are a much better option than the shiny aluminum. The architect and the building owner will be more in favor of this look. As far as we know, all manufacturers charge more for a color – other than silver – except Safe-T-Cover. We offer three different colors at no extra charge for standard enclosures. The three colors are Hartford green, Sierra tan, and slate grey. For an additional charge, we have a wide variety of other colors available.
Here is a link to the full list of color options available. Many people ask us how the color is applied and are pleasantly surprised. They are not painted and there is no risk of chipping over the life of the enclosure. We work with Pac-Clad®, the largest manufacturer of metal roofs in the United States. They apply a prefinished sheet metal coating of 70% full polyvinylidene fluoride to the aluminum. It was originally developed for use in abrasive environments but is also ideally suited for enclosures. For a custom enclosure, adding color typically adds 15%-20% to the price.
Historically, civil engineers place the water tap for new service as close as possible to the property’s planned driveway location. But with an above-ground backflow preventer enclosure to install, it’s much more sensible to think about the aesthetics and strategically place the water tap accordingly. Several jurisdictions have been using above-ground enclosures long enough that the planning review folks are already thinking about the enclosure’s impact at the beginning.
Seek to place the backflow assembly as close to the property line as you can, but consider the curb appeal. The property line doesn't exist solely at the front entrance or along a roadway. How often do you see the electrical transformer at the main entrance of the building? Or in the middle of the lawn between the building and the road? More often than not, the location of the transformer has been thought about and placed where it is not so easy to notice. Why? Because it is not aesthetically pleasing. Think about the trash dumpster and where those are typically located. It's usually in the back of the building with some type of disguise that keeps them from sticking out and taking away from the appeal of the building. Backflow preventers can be installed behind or beside buildings out of sight, but stay in line with AWWA recommended best practices. Below is an example of excellent placement.
Until a few years ago, most backflow preventers 3" and larger were large and long. First, there was a vertical riser through the concrete slab, turned 90 degrees and then a series of gates and valves, all oriented horizontally in succession, then another 90 degrees back down through the concrete slab.
The new “N-type” backflow preventer solutions turn the shutoff valves into the vertical plane and place the 90-degree turns within the boundaries of the shutoff valves rather than beyond them. The result is a much more compact assembly. With a smaller assembly, you get a much smaller backflow enclosure. In fact, the covers for these new designs are as much as 70% smaller than their predecessors. If your client has a choice, there is little doubt which version they'll prefer. Here are the two options side by side.
A great way to dress up your backflow enclosure is to wrap it. Your enclosure can be used to display your company logo, advertising, signs, art and more. The vinyl wrapping materials are made to withstand all types of weather conditions. You can wrap a backflow enclosure in as little as two hours and it will last years.
Your enclosure won't look like a plain aluminum box but instead, contribute to the visual appeal of the building and surrounding area. This is the most creative way to hide utility boxes. The only thing that limits you is your imagination.