To be exact, the name "Fernco" is a company that makes flexible couplings. It is not the actual name for a
flexible coupling. Fernco gets a free advertisement on this site because they're that good! There are other companies
out there that make comparable products, however.
Ferncos are designed to connect two pipes together. They are normally of two different type materials, but can be
of the same material as well.
The process of connecting pipe is quite simple. The length of the fernco is divided in half between the two pipes.
Simply use half on the one pipe, then tighten down the clamp. Then insert the other pipe into the remaining half and
tighten that clamp. That's all there is to it!
The picture above shows a fernco connecting some newer pvc to an old section of galvanized. Without this invention,
you would have to replace alot more galvanized, and use male-female connections to screw the two pipes together. Or
replace the entire length of the galvanized.
The picture to the left shows another extremely valuable advantage of the fernco adapter.
The pipe above the fernco was existing, while the pipe below was completely replaced all the way
out to the sewer. The problem would be how to connect the new pipe to the existing pipe when there was absolutely no play
between the two.
The solution was in the fernco which was the last fitting to be put together. It was put onto the
existing pipe, then was slid far up the pipe, well out of the way. Then the new pipe sections were built. The last step
was to slide the fernco down onto the new 4" pipe. This would have been impossible without the fernco and would have to
have been done a completely different and time consuming way without it.
One issue to be aware of is that of copper drain lines. They have a thinner wall, while the inside diameter remains
the same. This leads to the outer wall(where the fernco is attached) to be slightly smaller, requiring the fernco to be
sucked in a bit further than intended.
This does not really present us with a problem, except in the case of 1 1/2" copper drain line. In this case, the
difference is quite apparent. The 1 1/4" size fernco fits best on 1 1/2" copper. Generally, you would be connecting
1 1/2" pipe(pvc) to 1 1/2" copper. The better fit would be a 1 1/2- 1 1/4" fernco.
The fernco adapter has been a huge saver of time and energy in the plumbing world. This company also makes a large
variety of other products.