Help - Toilet Water Turning Brown!

[nigel]

We have two loos up stairs one in bathroom and one in en-suite - they are about 3m from each other, both empty into the same near horizontal soil pipe that empties into stack literally 500mmfrom the downstream toilet

Both toilets are on same floor level and same height - leave them for 12 hours or so without using and the water in pan goes brown - any ideas?

Is it allowed by building regs to fit two toilets this way as there can be no fall in soil pipe and muck in soil pipe must be draining back into pans

The loos/house was built 11 years ago - any ideas please? Many thanks all

 

[Paulus]

I believe you have answered your own question, backflow through soil pipe. You need to either raise the toilets or lower the connection to the stack.

 

[PETE 123]

Or put loo blues in cisterns then water will always be blue