Backwater valve in new homes?

Hi everyone, talked to this fellow and Just got this e-mail and wanted to
find out for sure what is what with the backwater valve.
Subject: Backwater Valve in new homes

> Hi Chuck,

> We just chatted on the phone and I already want to thank you for taking
> the time and answering my questions.
> My question is if Ontario has a requirement in the building code making it
> mandetory for new homes to have a backwater valve and if a properly
> installed backwater valve is something that we can check or verify the
> presence of.
> As I said over the phone it looks as though this is code in Manitoba and
> this web site shows that home owners in Manitoba ( at least in Winnipeg)
> are able to inspect and clean out their backwater valve.
> Of course I do understand as well that winnipeg is a flood plain area and
> they would have strickter requirements on this type of thing.
> Thanks again,

Chuck to answer your question ontario code Accessibility (1) every fixture ,plumbing appliance ,intercepter,cleanout,valve,device or piece of equipment shall be so located that it is readily accessible for use,cleaning and maintenance.This is from the 1997 code book

about all you can check is to see if its installed in the right direction of the flow. It should have and arrow on it indicating the direction. I’m assuming your talking about the drainage system here, and there is usually a compartment covered with wood or metal plate in the concrete floor close to the main clean-out. In our area, they place a sticker on the electrical panel to let the home owner know if one has been installed in the home.

If your talking about a back flow preventer in the water supply system, these too can also be installed backwards…just check for the directional arrow for correct installation.

although I think it’s a really good idea if one bulds a new home to install one, to the best of my knowledge there is no building code requirement in Ontario for new homes to have a drainage back flow prevention valve. However, if someone knows the relavant code section I could be proven wrong. Have not look at code in quit some time.

This device was invented by a chap in St Albert, Alberta and is required on all new homes in St Albert. It is recommended by the City of Edmonton. It can only be installed with the flow in the correct direction, If it is installed backwards it will stop the flow. It is designed to allow the sewer to vent and water to flow through. The valve is activated when water flows back. It shuts off. Hence the name “back flow preventer”. All other valves are called check valves at lease that’s what I call them just to keep it straight in my mind. Thus I know what I’m talking about.
I would be interested in knowing what other municipalities require them.
I think they should be added to all the building code

i don’t think that it is code but most comercial buildings in peterborough area the insurance companys are making it manditory that they install backflow preventors. No backflow preventor no insurance. That could be starting to flow toward residential as well.

The code seems to be a bit ambiguous on the subject. says
1 A backwater valve or a gate valve shall not be installed in a building drain or in a building sewer.
2 Except as provided in sentences 3 4 and 5 where a building drain or a branch may be subjected to backflow a gate valve or a backwater valve shall be installed on every fixture drain connected to them where the fixture is located below the level of the adjoining street.

I think that sentence 5 is the pertenent one here.
A subsoil drainage pipe that drains into a sanitary drainage system that is subject to surcharge shall be connected in such a manner that sewage cannot back up into the subsoil drainage pipe.
On one hand it says no and then gives 3 or 4 reasons to have them installed.

What Larry said plus; Appendix “A” A-[1] and A-[5]

The appendix clarifies this further.

Only clarifies for the ones that have the book?:frowning:

Protection From Backflow Caused By Surcharge
These requirements are intended to apply when in the opinion of the local authority having jurisdiction there is a danger of backup from a public sewer.

So I guess it is up to the local authority as to when and if a backwater valve is required.

If you ever need the “book” call me and I will loan you mine.


E-mail me your address and I will put one in the mail for you. Part 7 Plumbing Code book]

You may want to advise your clients to check with their individual municipalities. The city where I live passed a bylaw that states all homeowners must install a backwater valve at their expense if they do not have one. They also stated that as of a certain date they would no longer compensate any one who did not have a backwater valve and who was flooded because of a city sewer.
I think it’s a good idea to recommend one even if not required by law.

Thanx Mario, I owe you one.:smiley: :smiley:


Your welcome.

I hope you received it today, Canada Post said that it would be delivered today!

Yes, got it yesterday, what do I owe you?


Nothing. Enjoy!!!

Hey, guys! Recently I’ve read two posts relevant for the theme
Dr.Pipe Ottawa: Does Backwater Valve Actually Work For New Houses?
Why You Should Install Backwater Valves In Hamilton - DrPipe Hamilton
Hope, their will be helpful!

Yup check locally, in Edmonton they have been required for new homes since 1989, so if the house is in Edmonton and it was built after 1989 it will have one. Edmonton does not require updating older installs.