Many online sellers don’t abide by convention and I understand their logic. Although the one in my link eventually does quote the OD. You only have to look via Amazon, ebay and others and the majority quote 28.5mm ID. I guess it’s logical as it is the drainage pipe that pushes on to the caravan drain outlet. So if someone wants to find a pipe that fits the caravan waste outlet the obvious way is to measure the OD of the waste outlet which then gives the ID of the pipe they require. The OD, to a degree, is almost irrelevant.The pipe is 32mm as all metric pipes are measured in OD. You can buy it by 2m or 3m single lengths from Toolstation.
When I looked it was cheaper to buy a kit than the individual parts.And using some of Clive’s pipe you can make one of these with the white parts from most diy or Screwfix stores
But not in the caravan waste system drainage. Just search the ads. How many think of Toolstation as their first port of call for a caravan waste hose. I suggest a very few. But I admit leisure vehicles are a bit if a cottage industry. 😂Go to Toolstation or Screwfix and ask for 28.5mm ID waste pipe and most people behind the counter will look at you like you are out of your brain.
As for 32mm pipe and they'll ask you how many you want.
I was not saying how you approach a retailer or whatever, it is just that (with EU help!) asking for the OD without reference has become the norm.
I did mine 20 years ago with all the odds and sods collected over the years. Thanks for the heads up👍When I looked it was cheaper to buy a kit than the individual parts.
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28mm Waste Water Pipe Outlet Hose Easy Drain Away Connection Kit Caravan | eBay
Caravan Waste Water Pipe Outlet Hose Drain Away Connection Kit 28.5mm. 2 Off 28mm x 90 Degree Elbow ( 81325 ). 1 Off 300mm 28mm Waste Pipe. 1 Off 28mm Tee Connector ( 81327 ). Caravan Accessories. Waste Outlet Connection Kit 28.5m.www.ebay.co.uk
#3 shows solid pipe, not flexible, hence why some may consider a hardware retailer rather than a caravan dealer?But not in the caravan waste system drainage. Just search the ads. How many think of Toolstation as their first port of call for a caravan waste hose. I suggest a very few. But I admit leisure vehicles are a bit if a cottage industry. 😂
Certainly if I wanted a solid pipe waste drain Screwfix would be my first port of call. But that’s doesn’t detract from the fact that in my initial post the pipe was flexible and referred to as 28.5 mm by the leisure equipment retailers.#3 shows solid pipe, not flexible, hence why some may consider a hardware retailer rather than a caravan dealer?