Washer Standpipe and Trap height

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I posted this in the plumbing code section as well. I'm looking for some advice.

I'm a homeowner, running the drain/standpipe/vent for the laundry (clothes washer) in the basement. My house was recently underpinned and the floor lowered by 18 inches. The underpinning is essentially an enlarged footing that creates a curb that takes about 4 inches of floor area. This curb is getting in the way of the washer standpipe and vent.
In an old post, Terry pasted the following:
"804.1 All plumbing fixtures or other receptors receiving the discharge of indirect waste pipes shall be approved for the use proposed and shall be of such shape and capacity as to prevent splashing or flooding and shall be located where they are readily accessible for inspection and cleaning. No standpipe receptor for any clothes washer shall extend more than thirty (30) inches (762 mm), nor less than eighteen (18) inches (457 mm) above its trap. No trap for any clothes washer standpipe receptor shall be installed below the floor, but shall be roughed in not less than six (6) inches (152 mm) and not more than eighteen (18)inches (457 mm) above the floor."

I think that's from the UPC.
When I look up the NPC of Canada (which I believe is what is used in Ontario) the only wording around the drains for a washer is:
"Where clothes washers do not drain to a laundry tray, the trap inlet shall be fitted with a vertical standpipe that is not less than 600 mm long measured from the trap weir and terminates above the flood level rim of the clothes washer"

In the NPC there is no direction about the min/max height of the trap. I want to keep my trap ABOVE the curb so that I don't have to frame around the curb. So I want my trap to be above 18". As long as I keep my Standpipe 600mm (24 inches) can my trap be at, say, 24 inches....in Ontario?


In the Trades
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Berkeley, CA
Sounds like you found the applicable section of your plumbing code, and if it doesn't specify a height above the floor, then it is unregulated for you.

Cheers, Wayne
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