Location of toilet in bathroom

Should a toilet always be located against an external wall? If it located on an internal wall should extra measures/devices be used to prevent blockages.......

I know en suites tend to be located on internal walls but as a rule most of the toilets in the house are located on external walls!

AFAIK they tend to be on an external wall, as the internal wall has to be able to take the weight of the cistern (should not be a big problem) and the sound of flushing will be transferred through the wall into the next room.

Our main toilet is located on an internal wall ,about 18" from the external wall and we have never had any problems (in 17 years!). We live in a bungalow - don't know if that makes a difference.

There are no problems in locating cisterns on timber or metal stud partitions; such partitions are generally beefed up with ply or timber grounds to stiffen the construction. Where toilets are located on external (masonry) walls it's usually for reasons of plumbing and waste outlets. If fixing on a stud wall you can minimise sound transfer from the cistern by sandwiching a layer of resilient matting (like a cork tile) between the cistern and the wall.

Fit a silent fill ball valve to minimise noise from the cistern when filling.

All 3 toilets in my house are on internal walls so hopefully it's not a problem and the builders didn't make a mistake.