Preventive measure proves profitable

Sewer gas rising from floor drains might be an unhealthy nuisance for commercial building owners and homeowners, but for plumbing service contractors, it can produce aftermarket and service call add-on sales that can increase profits.

A common cause of sewer odours in floor drains is the evaporation of the gas-blocking water trap seal that prevents sewer gas egress through a floor drain P-trap. It is especially common with infrequently used drains. Once evaporated, the trap seal is broken, leaving nothing to stop the sewer gas from rising up into the occupant’s breathing zones.

Plumbing service contractors have four options to remedy this problem. The water-supplied trap seal primer consists of a vacuum breaker and works on a pressure differential concept. The drainage supply trap seal primer catches a more conservative quantity of waste water and directs it to the floor drain to keep it primed. The deep trap seal is longer, deeper and holds more water. The barrier-type, waterless floor drain trap seal protection device, which is the focus of this article, features a one-way membrane that acts similar to a check valve. The membrane is sensitive enough to open from the weight of just four ounces of water, but strong enough to stay closed and sealed to minimize evaporation and eliminate sewer gas odour.

The waterless floor drain seal does not require floor breakups or a water supply and needs no maintenance. Installers simply push-fit it into the drain pipe after removing the floor drain grate. A tapered rubber gasket around its circumference holds it tightly in place and also creates a tight, impenetrable seal between the device and the drain pipe interior. <>

Canadian Codes

Canadian codes and enforcement of all drain trap seal devices is vague at best and really up to the local jurisdiction, according to Julius Ballanco, P.E., president of JB Engineering & Code Consulting. The National Plumbing Code of Canada, which is loosely based on the International Plumbing Code and other authorities, calls for the protection of the trap seal via a trap seal primer valve “or equivalent.” Ballanco notes that the “equivalent” covers the use of a waterless floor drain trap seal in new and retrofit work.

Choosing the right waterless trap seal

CSA approval does not necessarily mean a local city inspector will allow the device or has even heard of them. The selection of a product tested and certified under ASSE-1072 can be a persuading talking point for code inspectors, because ASSE is the predominant certification authority for waterless floor drain trap seal devices.

There are different degrees of ASSE-1072 certification and it is the contractor’s responsibility to investigate which drain trap seal devices are fully-certified. For example, certification results will reveal some brands do not meet the requirements to withstand the effects of dirt, debris, floor wax, and mop strands, or are restricted to certain flooring materials. Generally, Ontario accepts ASSE-1072 certification, but some jurisdictions in other provinces may not. Aside from certification, the device’s appearance may reveal its quality.

A solidly built model with a sturdy membrane can cost anywhere from $45 to $60 wholesale and is recommended for a $15 mark up, which is a profitable aftermarket sale considering it takes a contractor less than one minute to install. For plumbing contractors, it can eliminate costly call-backs from an unhappy customer who paid hundreds of dollars to have a drain line cleaned and continues to smell sewer gas odours.