safe floor loading?

[ds82]

hi, i have two aquarium tanks upstairs that each hold 100litres, which i believe is 100kg each, they are both exactly 1m2 each and sit flat on the floor, ie no small surface area stand. they are next to each other in the same direction as the joists if you get my drift, so they ocupy the same joists, of which there are two. however i was downstairs and noticed that two of the joists have deflected somewhat, the plasterboards has bulged where each joist is. also i checked upstairs and the floorboards above the joist end ( ie where the joists overhangs the load bearing wall) appear to have raised significantly, i need to know whether this is a safe load to be applying to the floor, joists are 8 x2, 600mm centre's and span around 4m

many thanks in advance

ds82

 

[imroberts]

I'd say no, if the joists are bending

Are you sure the aquariums are only 100 litres? A tank 1m3 would hold 1000 litres which weighs 1000kg... a ton!

If the tanks are in fact 100 litres as you say, I wouldn't be too concerned about 200kg across two joists. If you consider two people on a bed or sofa wold easily weigh 200kg... a washing machine can weigh 85kg... it shouldn't be anything to worry about

 

[Static]

8x2 spanning 4m at 600c/c would fail under your loads as you say first in deflection then maybe stress if enough people are in the room.. you need to reduce the joist centres to about 300-400mm depending on the amount of movement in the existing it may just be simpliest to add a few extra joists between existing..
Or get rid of the tanks, or move them downstairs, or get smaller ones..

 

[dhutch]

I'd say no, if the joists are bending

Are you sure the aquariums are only 100 litres? A tank 1m3 would hold 1000 litres which weighs 1000kg... a ton!

My thoughts too.
- If ther 1m^2 and only 100l then they are only 100mm tall ?


Daniel