Pipe size for new supply - 25mm or 32mm?

[aa44]

I am about to build a new house and I will need to run a water supply pipe about 140 metres (uphill) from the water main at the bottom of the hill to the house. There is a house next door to the building plot and the guy there reckons that he gets about 3 bar from his supply pipe that runs a similar route.

My question is, should I run the supply pipe in 25mm or 32mm? The local utility (Scottish Water) specifies a minimum of 25mm. The house will be a decent size with several bathrooms, all fed from mains cold and an unvented hot water system.

Given the cost of digging up the field etc, the additional cost of 32mm over 25mm is very small. Are there any disadvantages in going for the larger size?

Thanks
AA

 

[Deleted member 105431]

definately go 32mm, you'll regret it if you don't!

 

[doitall]

At least 32mm by the sound of it.

 

[mickyg]

about 140 metres (uphill)
several bathrooms

32 minimum, I'd be tempted to go to 50

 

[Norcon]

I laid 150m x 32mm recently from the water main at the road. It branches at the back of the garage and continues into the property for about 10 meters in 25mm.
Supplies a large new build with four showers. 4 bar static.
Two of them are huge rain heads and the flow is astonishing to both of these concurrently. Mira excels with divertors are fitted.
Can't wait to get the rest online which should be within the next few weeks.

 

[bengasman]

As the price difference is negligible, go for at least 32 if not 50.

 

[Agile]

I am also inclined to suggest that you use 50 mm bearing in mind that the digging cost will be so high.

A 50 mm pipe will never give any problem from being oversized but a 32mm might.

Tony