water pressure and flow to new loft room

You'd loose about 1 bar of pressure for every 10 metres you go up, so pressure loss on a mains supply due to height probably isn't an issue.

(flow loss due to narrow pipes on long runs may be)

In message , " snipped-for-privacy@gglz.com" writes

Huh!

I have just said goodbye to a water board inspector who kindly measured our supply pressure. (done by removing the meter and connecting a gauge).

Result 5 bar or thereabouts. 8.45am so not exactly zero use static pressure.

My problem is that some tenants have installed an *under sink* water heater fed directly from the supply. For obvious reasons, these are fitted with a pressure relief valve which happens to operate a 6bar!

Late afternoon pressure clearly exceeds 6bar, grrr...

regards

In article , Tom writes

As others have said, the height should not be an issue on a mains feed but any extra simultaneous usage in the house might lead to disappointing results, you'll need to suck it and see.

You're not allowed to pump water from the mains (unless you're the fire brigade).

Thanks for the replies.... I'll see what happens. Certainly an upgrade of the water supply from the road sounds like the best option.

Any idea what size pipe should be installed?

Rgds., Tom

I played this game a few years ago. Basically took out a gravity fed tank based system, and installed a combi boiler when I converted the loft. We had a 1/2" copper main that had reasonable pressure but slightly limited flow rate (about 18 lpm at ground level).

The extra height and pipe resistance made the shower on the top floor less powerful than then first floor one, but not dramatically so (after all the difference was only approx 9' of head less). Performance was well in excess of what one would achieve with an electric shower for example.

Unless there is a pressing need to get the pipe in now, because access later will be difficult, I would suggest you wait and see. You may find it adequate for your needs as is.

In article , Tom writes

Pipe & fittings here:

If these are pressurised under-sink heaters, to they not require ( and come suplied with ) 3 bar inlet regulators?

Certainly, full-sized megaflos do.

In message , Ron Lowe writes

Apparently not.

This was installed by a plumber!

The cheapo Screwfix one I installed under our sink was made in Italy where the rules may be different. Same 6 bar relief valve but I wanted to use soft water to avoid clanging the thing up with lime and installed it in the hot water supply (vented).

Fitting a regulator would be easy enough.

regards