In the News - The Calgary Sun

May 29, 1986

"Don’t take city’s advice"

By P.R. Salmon

The city of Calgary is dispensing poor advice to homeowners, P.R. Salmon, president of Home-Alyze Ltd., tells Counterpoint

My Utility Statement this month from the City of Calgary includes an insert from the Engineering Department Sewer Division, entitled When the Raindrops Keep Falling, Falling, Falling.

While the pamphlet is informative on several points, it contains one piece of very bad advice – specifically, that floor drains should be sealed with a screw cap. Excerpts from the pamphlet are as follows:

• Ensure your floor drain, which is connected to the sanitary sewer, is capped when not in use – especially during heavy rainfall.
• Always keep your floor drain cap secured when the drain is not in use. The drain cap is designed to protect your basement should sewage back-up occur.
• Diagram of a basement floor section showing a floor drain, with perforated drain plate, sewer cap and backwater calve.

First of all, a floor drain in the basement is designed to protect against flooding from such things as burst water lines, faulty hot water tanks, overflowing sinks, washing machines and dishwashers and, of course, from Raindrops That Keep Falling, Falling, Falling. Spring run-off or severe storm conditions may cause water seepage in the basement through wall cracks, basement windows, under footings and up around the edges of the concrete floor, especially if surface drainage around the house is not perfect. If the floor drain is capped under any of these conditions, the basement could simply fill up with water.

The floor drain is a Building Code requirement designed to protect against unusual or inadvertent flooding and should never be capped. There is no way of foretelling when its use may be necessary.

Contrary to a statement in the pamphlet, the drain cap is not designed to prevent sewer back-up nor is there any suggestion in the Building Coed that it be left in place. Its purpose is to prevent concrete or other debris from falling into the drain pipe during construction and it should be removed when the perforated drain plate is installed.

Backwater valves are designed to prevent sewer back-up and should be the only device installed if there is some concern. The floor drain screw cap, if it is still in the house, should be removed and discarded.

The diagram showing both backwater valve and screw cap in place is a ridiculous configuration, as both devices have the some effect on sewer back-ups. Furthermore, it is labeled as “typical,” inferring that all or most homes are so equipped. In fact, most older homes do not have backwater valves. As a point of information, there are several types available, including an inexpensive ball float type that fits into the neck of a floor drain and can be easily serviced.

The other diagram showing a perimeter weeping drain connected to the storm sewer is also labeled “typical,” when, in fact, at least half the homes in Calgary, including many new homes, are not equipped with weeping drains or storm connections. Without a storm connection and perimeter weeping drains, the risk of basement flooding from spring deluge or rising ground water levels is higher, thereby underlining the necessity to keep the floor drain in operating condition.

If the city Engineering Department is worried about blockages in the sanitary sewer system, perhaps they should inspect and clean or repair the lines which specifically concern them, rather than trying to compensate with bad advice to home owners. Restricting the floor drain may not stop a sewer back-up in any case. The effluent might simply rise to the level of the basement toilet, shower or laundry drain and overflow in the basement anyway.

As a final thought insurance companies might take a dim view of intentionally closing the floor drain if they were asked to pay for flood damages.