Weight of water

12 May 2005
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United Kingdom
Sorry if this info is available elsewhere...but i cant find it.
How much does water weigh?

How much a 50 gallon tank of water weighs

I need this info to make sure i dont bring the ceiling down if i install a 50 gallon tank!
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isnt it as simple as a litre of water weights a killo 4.5 litres ish to a gallon

so 50 times 4.5 kilos=225 kilos i think :(
1 ltr water = 1 kg

And since I don't know how many litres 1 gallon is, the rest i up to you :LOL:

(And I'm sure it didn't take me 2 minuter to type this (see big-all just 2 minutes ahead of me) ;) ;) ;)

Or see here for exact litres (227,3 litres in 50 gallons)
jonblair said:
I need this info to make sure i dont bring the ceiling down if i install a 50 gallon tank!

You need to spread the load over 3 joists with marine ply or similar :D
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Thanks very much. With the info available, i can work out the weight of 50 gallon tank. i am rusty, did not realise 1 litre weighs 1 kilo.
The gallon contains 10pounds avoirdupois of distilled water :LOL: :LOL:
Thank goodness someone uses real measurements dia.

It also weighs 63 lb/cu ft if you have only a tape measure. A little multiplying exercise will also reveal 50 gallons weighs nearly a quarter of a ton!!!!
Only about the same as a couple of plumbers, and they usually stand on just the one joist while walking across the loft.

Broken Welsh coal averages 1 ton to 40 cubic feet.
I didn't want to be left out on the numbers....
average man weighs about 75 Kg, you could possition it over a supporting wall (if there is one) to avoid the cielling cracking.
Plumbers aren't average men. I can remember 75kg, just. Double that now with toolbox or a boiler under one arm.
Thanks to all who replied. One other conundrum, the ceiling joists are not your usual 4 by 2!. The tank is to be positioned in the apex of a chalet bungalow, where the ceiling joists are 2 by 2 inches, spaced 18 inches apart. In the section where the tank is proposed, the length of joists is 4 feet.
sorry to quote the figs in inches and feet...but i never decimalised.
In that case they will have one eighth the stiffness/strength of 4 x 2's so are completely inadequate for your purpose. Replacing them will I'm sure be difficult, but is probably the only way to go. Screwing another 2" on will not work!

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