Pipe diameter for new build

[_matt_]

Hi all,
I am in the process of planning for a 2 storey new build and have been told the standard pipe diameter for the internal plumbing is 1/2 inch.

I have concerns about pressure, particularly with a high likelihood of showers being used at the same time as other appliances.

I have heard that upgrading the pipe diameter may help with this so I would love any advice on this or other advice people might have on avoiding pressure issues as much as possible.

Thanks,
Matt

 

[Scott_D]

How many bathrooms will you have?
How will hot water be produced?

 

[_matt_]

Hey Scott,

2 bathrooms upstairs, powder downstairs.
the hot water unit that the builder uses is a Rinnai sunmaster solar 270L unit with a gas booster, we have the option to upgrade this to a 300L electric booster unit.

Cheers

 

[Scott_D]

Is this in the UK?

 

[_matt_]

Nope, in Australia

 

[Scott_D]

@oz-plumber might be able to advise

 

[oz-plumber]

Hi Matt,

Generally the pipe sizes are 3/4 mains for cold water and 1/2 mains for hot water.
This was standard when copper pipes were used.

Now with plastic pipe the internal diameters of the pipes are smaller, so an increase in size is required.
More importantly, some of the internal bore of the fittings are even smaller, so an upgrade if pipe size is required.

What I find interesting is the upgrade from a gas boosted solar system to a larger electric system is considered an upgrade.
In my books, a larger electric system would be cheaper than a gas boosted system.

Are you dealing with a volume builder?

 

[_matt_]

Hi Matt,

Generally the pipe sizes are 3/4 mains for cold water and 1/2 mains for hot water.
This was standard when copper pipes were used.

Now with plastic pipe the internal diameters of the pipes are smaller, so an increase in size is required.
More importantly, some of the internal bore of the fittings are even smaller, so an upgrade if pipe size is required.

What I find interesting is the upgrade from a gas boosted solar system to a larger electric system is considered an upgrade.
In my books, a larger electric system would be cheaper than a gas boosted system.

Are you dealing with a volume builder?

Hey,

Thanks for the reply.
Sounds like I need to talk to them about increasing the pipe size then.

I am a bit wary of the electric booster as I have heard that they run constantly to keep the water at 60 degrees (whether the water is in use or not) whereas the gas booster only runs when the water is in use and less than 60 degrees. Sounds like it might be cheaper upfront but possibly dearer in the long run?

Yes we are building with Boutique Homes in Victoria, so we are limited in what they will install unfortunately. I believe that they also offer an instantaneous unit as well, but I’m not clear on the pros/cons.

Cheers

 

[Timmy D]

Hey,

Thanks for the reply.
Sounds like I need to talk to them about increasing the pipe size then.

I am a bit wary of the electric booster as I have heard that they run constantly to keep the water at 60 degrees (whether the water is in use or not) whereas the gas booster only runs when the water is in use and less than 60 degrees. Sounds like it might be cheaper upfront but possibly dearer in the long run?

Yes we are building with Boutique Homes in Victoria, so we are limited in what they will install unfortunately. I believe that they also offer an instantaneous unit as well, but I’m not clear on the pros/cons.

Cheers

The electric must be connected to a thermostat and once the water is at 60c, it will stop heating otherwise it would go above 60c.