Isolation valve

[Spiderman]

When fitting isolation valves to hot & cold taps under the sink can somebody tell me how much pipe to cut off is it around an inch and also is it ok to use Ptfe tape as I don't have any jointing compound

 

[Whyme]

Measure the depth of each side of the valve, that will tell you how much to cut and no on the ptfe pal. thats for threads that need jointing not nuts and olives..

 

[Best]

Depends on which type of isolating valve you use. If it is the ordinary cheap & nasty Ballofix type valves, then it is about 1/2" to remove. Surely it is just a matter of you measuring how far a pipe goes into each side to find the centre cut off length?
Compress the olives & slacken back & put a couple turns ptfe over the olives to help seal them well. Paste is better.

 

[Spiderman]

Many thanks for the advice but thought I would ask as on a Youtube video the plumber said that he always cut an inch as a rule of thumb and as for the type of valves I guess they will be the cheaper ones as I will buy from wickes or online as I don't have an account at the big plumb suppliers

 

[Best]

Ignore the YouTube "plumber".
If you cut an inch off the pipe, the pipes would be slightly too short if there is no movement in them.
It is up to you what valves you use, but if you want or need better quality valves that will probably turn off properly & without leaks, even years in the future, then you can get full flow valves which also have better internal seals for another couple quid. Cheap ones will do fine though.

 

[Chalked]

Depends on which type of isolating valve you use. If it is the ordinary cheap & nasty Ballofix type valves, then it is about 1/2" to remove. Surely it is just a matter of you measuring how far a pipe goes into each side to find the centre cut off length?
Compress the olives & slacken back & put a couple turns ptfe over the olives to help seal them well. Paste is better.

Ptfe on olives! Nooooooooo

that's just for decorators who haven't got a clue.

 

[Spiderman]

Ignore the YouTube "plumber".
If you cut an inch off the pipe, the pipes would be slightly too short if there is no movement in them.
It is up to you what valves you use, but if you want or need better quality valves that will probably turn off properly & without leaks, even years in the future, then you can get full flow valves which also have better internal seals for another couple quid. Cheap ones will do fine though.

Many thanks. Can you please tell me where I can purchase them from and what names to look out for

 

[Best]

Ptfe on olives! Nooooooooo

that's just for decorators who haven't got a clue.

Well he did ask could he use ptfe as a sealant because he'd no paste! He is a diyer. :smile:

 

[Spiderman]

Well he did ask could he use ptfe as a sealant because he'd no paste! He is a diyer. :smile:

I asked about the Ptfe instead of jointing compound because a plumber on Youtube was using it and I wanted some expert advice

 

[Best]

Many thanks. Can you please tell me where I can purchase them from and what names to look out for

Depends where you are I guess. Plumb Centre or most other plumbing merchants will do both the cheap type & better types. Screwfix will probably do them. I will take a look & try to send you a link.