View Full Version : What's this for?

07-14-2010, 04:49 PM
OK, inspecting a new building for ADA compliance and found this in on two of the washbasins. Now they cut into the protective wrap and it is forward facing hitting a chair user right below the knees... but it also just seems a weird thing... it's a tiny url link...


07-14-2010, 05:13 PM
That would be for priming the floor drain below.
Without that, the p-trap water could evaporate.

If you ever go into a public bathroom, and it smells badly, take a paper cup and fill the floor drains with water.

Here is a picture of a p-trap with the inlet for the priming.


07-14-2010, 05:39 PM
Ahh Thanks Terry! It seems so much of an afterthought, oddly enough only one restroom had it in there despite this building having around 16+ restrooms.

07-14-2010, 05:42 PM
It is a trap primer, although they are usually attached at the rear, not the front. and you only need one for each floor drain. Other drains may have different means of maintaining the trap's seal.