Gas pipe and radiator circuit extension

[aryl]

Hi,

I am planning to extend a radiator circuit from my downstairs hallway in to the downstairs cloakroom. It will drive a small 1000BTU radiator.
I am pretty sure the incoming gas pipe goes along the hallway into the kitchen so when I make a channel in the concrete floor i DO NOT want to damage the gas pipe. A few questions,

1. How do I find out where the gas pipe is?

2. What is the best way of making a channel in the concrete floor?

3. How deep can I make the channel without damaging the waterproof membrane?

4. Any other advice on extending a radiator circuit?

Thanks!

 

[45yearsagasman]

Cannot you run the pipework on the surface?Saves a lot of heartache.Is there a rad above that you could drop off?

 

[aryl]

Unfortunately it is the only way and it needs to be buried into the concrete floor before the new tiles go on.