Floorboard / joist loadings

[Kevin]

Hi Group, I want to install a 6Ft fish tank in a dowstairs room (total weight about

800KG). I live in a 1930's semi and the floor joists are 2" x 4" and with a span of 16" the tank will be supported by 3 joists over a total length of 8Ft. I do not know the grade of joist.

Here is the question.....will the floor support the load ?

Thanks for any help

Regards

Kevin.

[Brian G]

Kevin,

Are you really sure about the joist sizes and 'span' that you have given?

Unless the 'joists' are laying on - or bedded into a concrete sub-base - then at 4" x 2" they are not strong enough to take any serious weight - that includes the furniture etc that you already have in the room - and you should *not* put that tank in.

With regards to the 'span', are you refering to the distance *between* the joists as they lay side-by-side as this measurement is normally 16" centre to centre?

The normal size ground floor joists for a 1930's dwelling would be around 8" x 2" and supported on dwarf brick walls with spans roughly around 12 or more feet and at 16" centres, with either herring bone or solid strutting to prevent them twisting.

If the above is the case, then I would suggest that providing you place the tank close to ends of the joists or over a dwarf wall the floor *may* carry the weight of the tank. But, at around 3/4 of an imperial ton, you may well be really pushing your luck, and a I would advise that you put a smaller tank in if you really want to watch the fish swimming around.

The alternative is to spend a bit of hard cash and get the floor reinforced under the tank!

Brian G

[Kevin]

Thanks Brian, Any chance of sending you a drawing, this will clarify things with regard to sizes / spans etc. (email me off group and then I can pick up your address).

The joist ends are suppoted on brick supports under the floor but I'm not sure about the sizes or length of the longest joists. The sizes quoted are in a recess where a fire place used to be.

Thanks for your input.

Regards

Kevin

[Brian G]

Snipped.

Kevin,

There is an e-mail on its way to you with four attachments with drawings showing a basic timber ground floor. It is from a Yahoo address and from briangrayuk.

If they lack the info that you want, please let me know via the group and I'll try and help.

Brian G