DIY gas installation !

[Basildog]

Definitely silver solder.
I had a yank tee but the pipe size of the bullfinch was wrong, so I joined a UK straight to it, can't see that ever failing even if I had used soft solder as the straight goes inside the tee.
View attachment 713486

Unfortunately your ingenuity is not permitted, it’s actually an offence to tamper with or alter a gas fitting
Whilst it may well work perfectly well you can’t do it

 

[olley]

Unfortunately your ingenuity is not permitted, it’s actually an offence to tamper with or alter a gas fitting
Whilst it may well work perfectly well you can’t do it

Sorry but that should be "shouldn't do it," not can't do it as I did.