We are having bathroom and shower rooms totally renovated. The installer, who seems to be very thorough, seems to tighten any connections, whether they be inlet or outlet, to a minimum, see where the leaks are after a day or two then re-tighten. The fittings are quality and he is relying on them being correct to create the seal.
If I were doing them I'd be using PTFE tape or some goo or other from the outset.
Just curious as to views of folk who have more experience of such things.
If you mean in compression fittings then they don't need PTFE tape and IMHO it can hinder getting a proper seal. On a clean pipe a compression fitting doesn't need to be super tight either.
I assume these are compression fittings? If so, a bit of ‘goo’ ( proper plumbers stuff) possibly but not essential. PTFE tape, no.
The ‘olive’ is designed to compress onto the pipe and ‘squeeze’ into the fitting. The thread provides the force to compress the olive and hold it in place. Water should not get as far as the thread.
As for retightening. I would always check after a day or so and tighten if any leaks spotted but I would hope / expect this to be minimal.
What sort of connections? It is easy to overtighten an olive style gland... ...as well as damage any straight fibre washers, by overtightening,.
Tape should only be used where the threads themselves supply the seal. Its useless with olives and flat washers and of course o-rings
Taps, bidet hose, basin waste. Seems as if his approach is right - find the minimum tightness that the connection is secure without ever overtightening.
PTFE tape (or hemp and paste) are only for tapered connections. I always use a smear of boss white on the mating face of an olive to be sure to be sure - the Irish approach :-)
Neither hemp nor boss white are approved for potable water, though similar things are.
No reason to use PTFE tape or "goo" on any screw on fitting in a bathroom. Olives and rubber or fibre washers are the seals on the fittings or pipe connections.
You must use PTFE (or equivalent) for cases where you need a seal on the threads. A common example would be the tail that screws into a radiator that the valve then fixes to. Getting a garden tap to screw into the wall mounting plate with the tap pointing down is also an art that can rely on copious amounts of PTFE to get the thing to lockup tight enough at the required angle of rotation.
Compression joints make a proper metal to metal seal using an olive driven into the gap between the fitting and the pipe - the threaded part of the connector only provides the clamping force to squash the olive into shape, and hold the joint together mechanically.
(There are some very very rare cases where a turn of PTFE under/over an olive can let you remake a join where there is a nick or score in the pipe that is preventing it from sealing normally (I recall needing to use this technique once only!).
You can also use PTFE on the threads of a compression joint as a
*lubricant* - making them easier (and quieter) to tighten in a confined space with short spanners etc. (Something like Jet lube V2 jointing compound applied to the threads would achieve the same result).Plastic plumbing fittings on things like sink wastes usually use a rubber O ring to make a seal - these need to be "tight enough" - tighter is no better. Things like flexi hoses that connect to modern taps also seal with an O ring, and the caution against much more than hand tight (since it would be easy to kink the flexi bit). Traditional tap connectors, and inlets to cisterns etc, usually use a fibre washer to seal. Again, tight enough is good enough.
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