We have recently moved to a smaller place, cheaper to heat etc and it’s got a combi boiler. Was told it’s cheaper to run better for the environment etc. we can not believe how much water we have to run off before the hot water comes through. It’s a full sink of water before the hot come through. It must be right as the in-laws is exactly the same, she makes the bed or puts the hoover around while the water comes through on her shower. It seems an awful waste of water to save gas.

It all depends on where the boiler is with respect to the tap, my son's boiler was in the kitchen and within a metre of the sink and was almost instant, in my last house it was 5 metres to the kitchen and it was a good 30 secs but the furthest bathroom was 20 metres away and took an age, as at the time I lived in the West of Scotland and water wasn't metered and in abundance so saving gas was the priority.
The diameter of the piping is also a consideration, if the boiler was changed from a standard boiler with a hot water tank the piping could be 22mm which will waste more water, replacing the piping in 15mm plastic is reasonably cheap as a DIY project if you can easily access the pipe runs, i.e easy under floor access, with plastic piping, if you can do Lego then you can do plastic plumbing. my PC is slightly to the right of Genghis
2012 HSE SD4 In Orkney Grey now gone, best car ever.

Just a driver wrote:

We have recently moved to a smaller place, cheaper to heat etc and it’s got a combi boiler. Was told it’s cheaper to run better for the environment etc. we can not believe how much water we have to run off before the hot water comes through. It’s a full sink of water before the hot come through. It must be right as the in-laws is exactly the same, she makes the bed or puts the hoover around while the water comes through on her shower. It seems an awful waste of water to save gas.

It’s our first time with a combi only ever had normal boilers before. Plumber came out and said it’s normal and nobody uses a kitchen sink for hot water, just put it in the dishwasher. I guess at our age it’s cheaper to waste water than pay plumbers to alter it. We was just surprised.

Another thing with a modern boiler, the pilot is 'nonmaintained' in other words, the flame is completly extinguished when there is no demand. So everytime there is a demand for hot water, (If the heating is off) it has to go through the ignition process.
You can save some water by not running it so quick whilst waiting for the hot to come through.

Just a driver wrote:

It’s our first time with a combi only ever had normal boilers before. Plumber came out and said it’s normal and nobody uses a kitchen sink for hot water, just put it in the dishwasher. I guess at our age it’s cheaper to waste water than pay plumbers to alter it. We was just surprised.

There is normally a setting that keeps the Combi Boiler Heat Exchanger at the the Hot Water Temperature when on Standby.
On mine it is set by rotating the Hot Water Control Knob fully clockwise, then back to selected Tap Water temperature.
This should speed things up as you will have instant hot water at boiler outlet.
I do not use that setting as for 6 months the Central Heating is keeping the boiler internal water warm anyway. FL2 XS SD4 Auto 2010 2012-2017 (21k - 91k miles) (MY2011)
FL2 Metropolis SD4 Auto 2014 2017- (16k - 77k+ miles) (MY2015)
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@Ian - Thanks for that - I didnt know gas combi boliers had that facility Jules

All valid points.
Depends on many variables.
Type of boiler, not all have a pre heat function.
Distance to the various outlets.
Quality of the installation. Good quality pipework with few restrictions make a difference. Now at the point when I learn something new something old is lost out the other side !
Now retired so it doesn't matter anymore.
Freelander now gone.