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Discuss Vent pipe into cws in attic in the Plumbing Forum area at PlumbersForums.net


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So the cws in the attic needs to be moved a few metres. Is it ok to run the vent pipe across from the existing pipe work with a slight rise to where the new position of the cws is?
Please tell me what the best practice is here?


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Yes, it is fine to extend the cwt vent pipe. It has to be a minimum height above tank. There is a formula for this.

Just be sure to give the pipe a constant rise before dropping down into tank.
I would advise to use copper because plastic used as a vent pipe is very prone to being accidentally pulled out of tank and could cause a flood.
Clip and insulate pipe.

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