Hi wanted a bit of advice. I thought all waste pipes needed some type of trap U bend, P bend, S bend etc.. I pulled off the bath panel and noticed that my bath has not got one? The pipe from the bath goes into a hopper outside, where as the shower, sink and toilet all have traps and go into the soil pipe. The properties on the street are old (around 120 years) and the street doesn't have separate rain water and waste water drainage. I've never had any smells or issues with the bath but should there be a trap?