Pipes in dry-lined wall.

[kdband]

Hello everyone

I recently had a new gas boiler fitted. When they were doing it, the chaps agreed to chase out the plaster and run part of the pipework in the dry-lined wall, so that I can cover over it later and don't get ugly pipes/boxing running down the wall. When they did it, they wrapped the gas pipe in yellow tape down the entire length that will be buried. I'm not entirely sure why they did this, my guess is so that the copper doesn't react with the plaster when the channel is filled.

I now need to do something similar with water pipes. The questions is do I need to do the same thing, i.e. wrap them in tape where they will be buried? Also is there a particular kind/colour of tape I should use for a water pipe? To my eyes, the stuff they used for the gas pipe looks just like electrical insulation tape.

thanks.

[mark]

If they felt a need to protect it from plaster or whatever they should have used this:

[Trevor Smith]

> mark I think you will find that yellow is an identifier for a gas feed pipe as green is for oil. Trevor Smith

[The Natural Philosopher]

Dunno about gas, but water pipes, especially HOT water pipes, should be sleeved with something. Best is slip on foam insulation. Then taped up. Otherise you have two or three potential problems.

1/. expansion and contraction will cause creaks against wooden studding, and may in fact split plaster laid over. 2/. incoming cold mains water is enough to lower the temp of the pipe, and if not thermally and to an extent vapour barriered, may cause condensation on the pipe when the air is steamy and warm. Add that to plaster, and you have a recipe for corresion. 3/. Its already easy enough to drill through pipes in walls etc. Adding an inch of foam at least gives a BIT of warning :-)

Hover I am confused. A dry lined wall is not generally full of plaster..?

If you are running water pipes in studwork, you can insulate or not really. In internal walls CH pipes just heat the house anyway, or if you have insulation behind the studwork on an external wall, then the pipes should be surrounded by that anyway Although plastic foam never goes amiss.

[kdband]

It's not a feed pipe, it's between the meter and the boiler. The only part of the pipe that is taped is where it will be buried in the wall, hence the reason I assumed it was done to protect it from any plaster/ filler, but I could be wrong, there could be another reason why they've done it.

No, the wall is dry-lined, with 1 inch thick polystyrene then boarded over, but it now has a 2 inch wide channel running down it with a gas pipe in it. I think the easiest way of making good is just to fill that section with plaster/filler, it is only a gas pipe so expansion/contraction shouldn't be a problem. I do take note of that point in relation to the water pipes though, so I think I will cover it with foam insulation.

[Dave Liquorice]

Yellow for gas and blue for cold water are fairly standard but green I've not seen for oil, the plastic coated pipe for (domestic) oil pipes is white. Green in the ground is telecommunications as in cable TV...

[Trevor Smith]

I stand corrected

[Dave Liquorice]

I wouldn't rely to hard on that info. I'm reasonably sure a shade of green is something to do with hot water, can't remember if it's flow of a primary circuit or domestic hot water (the stuff that comes out of taps).

I get the feeling it's one of those things where there are many "standards" depending on context, in buildings or under ground etc.