Dreading cutting into the mains pipe!!!

[RodddersW]

I'm going to have a go at plumbing in an ensuite (Shower, Sink and Toilet)
The house is a bungalow and all pipes are easily accessible underneath the floor.
I'm not too worried about using the compression fittings and the drains but am a bit nervous about actually joining it up to and cutting into the mains pipe!
How do I do this?

 

[Burnerman]

No particular problem with that so long as your mains stopcock is fully working.
For the mains cold the pipe is likely to be 15mm copper, for the hot supply you need to determine whether the pipe is 22mm or the older 3/4".
Break into the pipes where you are sure they are undamaged and nice and clean before you get in there with the pipe slice!
Add isolators to all of your appliances for future maintenance.
John

 

[longdogs]

You can drain the pipework at the lowest tap (probably all of them in a bungalow ) When the tap has stopped running you know that you can cut into the pipe supplying it. There will still be some water as pipes hold a surprising amount but just drain into a container. If the pipes are under the floor then you don't need to worry too much anyway.

If you have a combi boiler, turning off the main stopcock will stop both hot and cold water. If you have a cold water storage tank, you will need to either drain the tank, turn off the gate valve (if it works) or bung the hole with a rubber bung available from plumbers merchants.

As burnerman says, add some full bore isolation valves so that you can turn the water back on whilst you are fitting the en-suite.

ps. I always carry a couple of speedfit stop ends in my pocket just in case anything unexpected happens.

 

[RodddersW]

Thank you for the advice! I've been sorting out the waste pipes today and will be going for it tomorrow. I'll let you know how I get on!