We have a fiberglass, standard-sized bathtub that leaks into the basement. Seems our very old mother fills the tub, gets into the water and send water into the overflow connection on the end of the tub. Water pours into the basement. I can inspect the bottom of the tub in the trap area. I do not think the tub is cracked. When water leaves the tub through the drain there is no leakage. It appears that during an overflow event, water runs through the overflow, leaks through the connection between the tub and the overflow pipe, runs down the side of the tub and into the basement.

I removed the overflow plate on the end of the tub that includes the lever to close the drain. The plastic overflow pipe that connects to the tub has a groove around the edge that forces the pipe to center on the tub opening. There is no gasket between the edge of the pipe and the outside of the tub. I went to 2 plumbing shops and was told that the ‘overflow kits’ do not contain a gasket for application between the outside of the tub [which is rough fiberglass] and the overflow pipe. I do not remember if the outside of the tub at the connection with the overflow pipe is finished to provide a good seal with a gasket. They sold me a thick beveled gasket to place between the inside of the tub and the overflow cover plate.

Is this the best solution to this overflow leakage problem? Are gaskets available for placement between the outside of the tub and the overflow pipe? What is the name of the gasket?

In the meantime, Mom has been instructed to keep the water level below the overflow outlet!!!!

 

LKV1, Welcome to the DIY Forums.
I cannot see how a gasket on the inside of the tub would stop the overflow from leaking. It has to let the water go into the overflow pipe and thats where the problem is. Check at a Home Center or hardware and you will see the gasket included with the overflow piping. Not sure if you can buy it seperate. You could run a bead of silicone around it and then pull it up tight with the mounting screws. Good luck.

 

The gasket between the overflow and the tub is between the overflow flange and the outside of the tub. I purchased 2 schedule-40 overflow kits at Home Depot recently (because I messed the first one up during assembly). Every kit offered had a big juicy gasket with an exploded view showing it on the outside of the tub at the overflow hole. The tub I am working in is an acrylic-over-fiberglass unit (Kohler Devonshire). The area on the outside surrounding the overflow is smoothed at the factory to accomodate the gasket. Hey, you could save water by having someone shower in the overflow water as it falls in your basement. Nothin says clean like second hand granny water. Sweet.

 

There should be a gasket on the over-flow where it contacts the backside of the tub [not the inside], whoever told you that there shouln't be one dosen't have a clue. If there is not an access panel behind the tub you may have to use silicone like majic says. They do make over-flow replacement gaskets. Luck.

 

Hi, You have the correct gasket. thick on one end.The gasket is located between the overflow pipe and the tub. This is how I change that gasket, remove the overflow cover inside the tub take a screwdriver and gently push the overflow pipe away from the tub and remove the old gasket.Slip the new gasket over the screwdriver the push the pipe back and slide the gasket into place, thick side down then reassemble the overflow plate.
Good Luck Woodbutcher

 

The gaskets are certainly available seperately. Look here.