We have been living in a brand new build for the last 10 months. Two months ago we noticed a smell of imonia coming from our upstairs bathroom, it did'nt take too long for us to realise that the smell was coming from the toilet pan. I couldn't understand it, as I am very particular with keeping our toilets very clean. It became evident that regardless of how clean the toilet was, the smell was present, even after a flush, the water seemed to stink. The same vile smell is now invading our bathroom on the middle floor of our home, and I'm really at my wits end. Our property is still under 'defect period' so every repair is taken care of by the developer. My concern is that any plumber sent to investigate the problem will fob us off, as they are all still on this site, employed by the developer. Advice would be much appreciated :)

Don't quite know what you mean by "the toilet pan" Toilets sit on a solid floor surface and are not normally on a pan. Could be a bad wax ring that leaks sewer gas but that doesn't smell like Ammonia. Sniff around the base of the toilet and see if the smell is more evident there. If so, have the builder tighten the base mounting bolts. Since you are under the warranty period, don't you do it because if you break the base it's your problem. If that doesn't cure things, ask for a new thicker wax ring.

Do you have kids or elderly living with you?