What exactly is a “backflow preventer”?
What is its function?
I am installing a roman tub faucet for a “jacuzzi” tub. Home project.
Is this essential?
Thanks from Alaska.
What exactly is a “backflow preventer”?
What is its function?
I am installing a roman tub faucet for a “jacuzzi” tub. Home project.
Is this essential?
Thanks from Alaska.
Fine Homebuilding is excited to be the official media partner of the 2024 Building Science Symposium series! This event offers builders, tradesmen, architects, designers and suppliers to discuss topics ranging…
"I have learned so much thanks to the searchable articles on the FHB website. I can confidently say that I expect to be a life-long subscriber." - M.K.
Get home building tips, offers, and expert advice in your inbox
Fine Homebuilding
Get home building tips, offers, and expert advice in your inbox
© 2024 Active Interest Media. All rights reserved.
Get home building tips, offers, and expert advice in your inbox
Become a member and get instant access to thousands of videos, how-tos, tool reviews, and design features.
Start Your Free TrialStart your subscription today and save up to 81%
SubscribeGet complete site access to expert advice, how-to videos, Code Check, and more, plus the print magazine.
Already a member? Log in
Replies
It's a little device that threads on your faucet to prevent any water from backflowing back into the pipe, so you don't get any contamination. This looks like a pretty good explanation: http://www.irrigationtutorials.com/sprinkler08.htm
Surprisingly, it turns out there's an American Backflow Prevention Association. http://abpa.org/
Surprisingly???
Over here a separate license is required to install BVD's. You'll notice that almost all commercial/industrial areas have them somewhere on the property to separate out their water from the municipality general water supply. BVD's are everywhere, expecially in low pressure areas and alot of codes require them. It can be a very complicated subject, for example some areas will not allow double check system, but require only AVB's. An Assoc. is the only way to keep up to date on regs and products.
Perhaps I should have said interestingly instead of surprisingly... :-) I've seen plenty of backflow preventers on construction projects (I'm an EE who works on municipal water projects.) I understand why they are used but as a non-plumbing person I didn't know there was that much to them.
Edited 1/6/2006 11:05 pm ET by Stuart
Thanks for the good info. Kind of what I thought. My situation: rural home with its own well and septic system. This install is a tub faucet for a second story bath. Unnecessary in this application. Onward!
Jim
" My situation: rural home with its own well and septic system. This install is a tub faucet for a second story bath.Unnecessary in this application."IF NEEDED! then it would still be appropriate as you could contaminate the drinking water in the house.However, it is not needed in this case.In most cases there will be an air gap between the spout and the the flood rim of the tub. That will prevent the waste water from ever getting into the supply lines.Now hand shower attacments like these do need one and the end can end up in the tub water.http://www.vintagetub.com/asp/feature_item.asp?cat=78&subcat=35And the sell a vacum breaker just for that reason.
Edited 1/7/2006 12:35 am by BillHartmann
I agree with Bill H, just because you are rural, on a well, or are residential doesn't alter the siphoning principle. Most fixtures today for these applications, all are supposed to, have vacuum brakes. However, a flexible shower wand dropped into a sink or tub can be a problem, especially on an upper floor. You will probably have safe fixtures and installation, but the attention and prevention of siphoning can't be stressed enough. It's one area to over kill.Never serious, but always right.
Sorry, maybe I jumped a little hard, but this is one area I feel strongly about. I do irrigation design, and repairs and try to keep up on the laws. Always keeping in mind that h20 will be the oil of the future, sounds like the WaterBoy, oh well. Living on an island our water is very limited and so many system are installed with no BP of any kind. Also, no inspections of irrigation system installations is required and no backflow is required as a stub out during initial construction. The laws are screwed up, but the idea is right, protect the water.
Backflow Preventer are just what their name implies, they stop water from going backwards. The idea is that at times syphoning can occur from a contaminated source and flow backwards into the main water system, thus contaminating your drinking water. Normally you find them separating out the irrigation system from your house supply and on each exterior hose bib. If the pressure to your house is lost for some reason a hose lying in a puddle cannot back syphon from the puddle or pool back into the water supply and contaminate your house and all the other homes on the line. They can be expensive double check preventers, atmospheric vacuum breakers, or simple flap valves inline. I'm not quite sure what you mean by a Roman fawcet, but as long as the spout is above the water line I see no need for a backflow device.