In my master bedroom in my house there’s a strange sewage smell coming (what I think is) from the ground area, but only during the hours of 9pm PST and would last about 30-45 min. I would call a plumber, but kinda hard to source where the smell is coming from if it only occurs during that time. Also there would be some days where there is no smell, then there are some days where it is a very awful smell.
Anyone have ideas what it could be? and who i should contact?