My cellasr drain is made of cast iron and is about 35 years old. It is connected to a perforated plastic pipe that is installed around the foundation footings and also under the cement cellar floor. On occasion a stron rain storm will fill this pipe faster than it can drain which causes the water to backflow into the cellar. The cast iron drain has a 6.5" cover with perforated holes in a circle around it. It has a 2'5" inside diameter drain hole dropping into the plastic pipe. I can not find a back flow preventer with this dimension. Is there a solution to this, or will I have to break this drain out and install a new plastic one with a 2" or 3" hole? Any suggestions will be appreciated as to what to do and where to purchase it.

They make a floor drain check valve called a "FloodGuard", (see image) However they only come in 2 and 3" sizes. I will search the net for a 2 1/2" floor drain check valve but don't hold your breath. Regards, Tom

If none is available in 2.5", what do you remmend I purchase, once I have the cast drain removed. Some of the plastic drains have a u trap, which will not fit in the hole where the cast drain comes out of. Thanks Dave

You might start your search here Flood guards for floor drains - check valve to prevent flooding from FAMOUS PLUMBING SUPPLY (http://www.plumbingsupply.com/floodguard.html) I have not seen a 2.5" cast pipe, where do you live?

Hey Dave,
Sorry but Flood Guard floor drain check valves(see image) only come in 2 and 3 inches.
Bob, Dave's referringto the 2.5 inch opening in his floor drain. Not the size of the drain pipe.

Regards, Tom

You are probably right Tom. By the way, Flood Guard comes in 4" too, I believe.

You are probably right Tom. By the way, Flood Guard comes in 4" too, I believe.

They do Bob, But it's not applicable in Daves case. Regards, tom

For everyone's information, I purchased a hard plastic backflow preventer and some rubber parts to try to fashion a fit. As it turns out, the backflow preventer with a 1 1/4" threaded top end and a 1 1/2 " bottom end had a 2 1/2" center which housed the flapper. It fit the hole so tight I had to gingerly force it in with a rubber hammer after I cut the top threaded portion off. I filled the very small crack around the fit with hot melt glue and I am done. It fit so tight I do not feel any back water pressure from underneath could ever force it back out. Now I have a few extra rubber parts to take back and the entire thing costs $2.95. I thank everyone for their responses, which gave me confidence to try something anyway before I tore out the old cast iron drain. Thanks! Dave

Kudos Dave for thinking outside the box. Sounds like you have everything under control. Good work! Tom