what is meant by the "head of water" phrase? I am looking into fitting a shower and on it, it says I should have a min 2m head of water. I have an old back boiler on the ground floor, with a hot water tank on the first floor and a cold water tank in the attic. The bathroom is also on the first floor. Which water levels need to be 2m apart? Thanks for any help.
it means you need a distance of two meters between the top of the shower head and the bottom of the cold water storage tank (cistern) in the loft
The head refers to the vertical distance water falls to provide pressure. In practical terms for a shower it is the distance from the shower head to the base of the cold water tank. The minimum distance required for a decent gravity shower is 1.5m (5 foot). Most showers suitable for gravity feed have a minimum pressure of 0.1 bar. If the shower you have says more than this (0.2 bar) you might find it difficult to obtain enough pressure for the shower to work properly. In any case, you will probably need to raise the cold water tank. If you do this remember that when full of water a cold (50 gal) tank weighs in at 500lbs and needs to be supported accordingly.
ok thanks for the help... Guess with the cold water tank on the floor of the attic an me being a pretty tall chap by the time I have a shower I will be lucky to have 30-50cm clearance plus the attic is not that tall so would only be able to raise it by a meter or so... guess a booster pump is on the cards and a call out to the local plumber!