Hi i have just baought a property in which there is a saniflow toilet upsatirs. I am planning on removing this and putting in a proper soil pipe as there is enough drop to do so but i have noticed that i dont appear to have a soil vent anywhere. And I was wondering does the soil vent have to be vertical or can it have bends in it. I ask this because the route i have thought about using will need 2 90 degree bends.