Combined Overflow

[broxy]

Can the cold water cistern and F&E cistern share the same overflow,
ie f&e teeing into cold water overflow.
I'm pretty sure they shouldn't but my mothers local housing authority say it's just fine.

 

[Boilerman2]

As long as the water can't transfer between tanks, and the pipe is sized to take both tanks into account then no problem, but as the overflow would have to be 1" diameter, two separate overflows would be easier and of course "Best Practice"

 

[broxy]

It's just standard 3/4" overflow. Don't know why they just didn't put 2 overflows out, the holes were already in the fascia board.

 

[seco services]

local housing authority

if it's their plumbers you've answered your own question.