I would agree but I am not an expert in physics, so I am happy to be
proved wrong. I suppose the point is that whilst it might not be the end of the world, if you are DIYing, you may as well DIY it properly and minimise as much heat loss as possible and I suppose the losses all add up so that several small losses equal one big one over the whole system.
Thanks. Pipe insulation isn't very good, as you increase the surface area by using thicker insulation you loose more heat because of the much larger surface area.
That is why the surface area of 15 and 22mm pipe for the same result by the same manufacturer is the same diameter.
The amount of water in the 22mm pipe is about 7 times as much as the 15mm pipe and it takes a lot longer to cool.
The 15mm pipe cools more quickly as it holds a lot less heat, so it needs more insulation.
If you take a room at 22C and a pipe full of hot water at 70C , a uninsulated 15mm pipe in still air looses 55 watts per metre, a 22mm pipe losses 60 watts, as the speed of the surrounding air rises so the heat loss increases, this is an horrendous amount of heat loss.
That insulated GLC standard 15mm pipe looses 20 watts per metre. Check the length of your pipe runs and that amounts to a great deal of wasted heat over a year.
Insulation really saves and is noticed, when hot water is sitting in a pipe to the kitchen sink, the slower heat loss due to thicker insulation means that there is less hot water wasted when you turn the tap on. You avoid the situation where the previously hot water is now cold and you have to run off half a bowl of cold water, before the hot water arrives from the tap.