How much hot water for showers calculations!

country home

ok lads, sick to the teeth of deciding what size hot water cylinder to get. . 300ltr or 500ltr, or 300, or 500. . .

to make a long story short, it went back and forth and its now a 300ltr.

both plumber and local plumbing supply company agree that 300ltr is more than enough,

hot water will be for sink/basins and most importantly bath and showers.

5 basins
1 sink
5 showers
1 bath.


what worried me most is the showers.. . . how much would water are these babies going to suck up. . . so, . . i took a milk carton, 1 ltr. . and went to the two diff showers we have in the current house. 1 is electric, , , a piddle type thing, although if u know no better ud think it was fine. . . and the power shower type then we have in the main bathroom.. .
here are the results. ..

power shower. . . . to fill a 1ltr carton it took 5.5secs.
electric shower . . .to fill a 1ltr carton it took 10 secs

so based on this. .
a 10 min shower in the power shower will eat 110 ltrs
a 10 min shower in the elecrtic shower will eat 60 ltrs


I wont have an electric shower so no point in looking at the piddle machine.. its the pumped one id be look at pressure wise. . . as the house is all pressurised. . .

3 questions,. . .
Are my calculations accruate to suggest a tank size?
is 300 ltrs enough.
is bloody ten mins way too short for a shower. . . right now i seem to take my time. . id say its more like 20 mins. .

country home

first thing i can add myself to this is, u dont use purely hot water when showering. . . ud scall urself. . . so in that sense, maybe cut off 25% maybe???

slavetothegrind

i would think 300 litres is plenty unless you predict all 5 showers going simultaneously for 20 mins?

I take it the showers have thermostatic mixers on anyway to avoid scalding?