Could someone please put this to bed...

[OtaCustes]

Hi,

I have been looking around the internet trying to find the answer to what I thought to be a simple question, which is when to you use jointing compound and when to use putty (plumbers mait).

I thought, more than likely incorrectly, that jointing compound is used on pressure systems, non-potable like heating where compression joints are used (around olives) and putty was used in compression joints or sanitary fittings on potable systems.

Is this correct? All I can find are people who either don't know why they used, probabily the first thing to hand or people who think they're plumbers.
Can someone finally put me to bed on this please?

Thanks

 

[ChrisOxford]

You've opened up a can of worms there!

There are regular "scraps" here about PTFE, Plumbers' Mait, Fernox LS-X, Hawk White, Boss White (which to some people is a generic name for something which is suitable for potable water too) and so on

Let battle commence

 

[theheatinghelper]

ive always been of the opinion the an olive should do its job !! but you can always help to eliminate leaks ....if your new to this lark then its just which ever you choose ... trial and error but personally id only use plumbers mait on a multiquick around the stack pipe , ive have used boss white on toilet doughnuts with superb results but in the same breath ive used lsx and also "nothing" .compression fittings , if ive got some loose by i might smear a bit on the inside of the iron "the bell" of the fitting (all my own terms i might add ))) but i wont break my back to find some but i`ll always use the right stuff on gas ; )
oh and ptfe on rad tails and male irons i might add some more in a bit lol

 

[kirkgas]

plumbers mait is to be used on waste pipes etc, when you put plastic into a cast faucet you can use rope and plumbers mait, it is supposed to stay flexible where putty hardens, it is never to be used on plumbing pipes or hesting pipes, thats where the other jointing materials are usually down to personal choice, ie ptfe tape or suitable jointing compounds