This must be the easiest question to answer but I'm a little confused!!
In my two storey chalet bungalow, I've had the upstairs loo removed for a couple of days prior to a new loo being installed. The connection to the loo inside the bathroom is therefore temporarily a big open pipe joining the internal soil pipe. I can't believe that the main sewer is odourless, so why can't I smell sewer gas at the mouth of this open pipe. The soil pipe has a vent at the top, above the roof, but surely, sewer gas smells rise from open sewers and thus, sewer gas must be lighter than air. I'd therefore expect some smell wafting upwards into bathroom.....
Please could somebody point out the flaw in my thinking!
In my two storey chalet bungalow, I've had the upstairs loo removed for a couple of days prior to a new loo being installed. The connection to the loo inside the bathroom is therefore temporarily a big open pipe joining the internal soil pipe. I can't believe that the main sewer is odourless, so why can't I smell sewer gas at the mouth of this open pipe. The soil pipe has a vent at the top, above the roof, but surely, sewer gas smells rise from open sewers and thus, sewer gas must be lighter than air. I'd therefore expect some smell wafting upwards into bathroom.....
Please could somebody point out the flaw in my thinking!