External size of 1/2in copper pipe

[zinnia48]

I wonder if someone can help me by telling me the external diameter of 1/2in copper pipe is in mm, I have a mixture of metric and imperial piping in my bungalow, I know the external diameter of 3/4in pipe is 21.5mm. I know u can use ordianary 15mm compression joints, but am thinking of using push fit, for some tiding up process and am not sure if 15mm push fit will work on imperial pipe?, I have some metric/imperial push fit fittings if not. hope this makes sense to u plumbers

 

[kevplumb]

15mm = 1/2""" bar a gnats arse

 

[zinnia48]

But will that "gnat" mean that u can't use 15mm pushfit fittings on 1/2in pipe?

 

[Teahead]

1/2" = 12.7mm or is this the internal diametre. if so is copper pipe really 1mm wall thickness

 

[ChrisR]

1/2" is bigger than 15mm and I wouldn't use it with 15mm pushfit. If you get a gripper ring split the fitting can come apart. Some of the makers do converters between 1/2 and 15.
I'd just use compression to convert - cheaper and more reliable.