If your situation requires a secondary bund click for Explanation then a vertical probably will have no space saving advantage given the size of the necessary bund.
Apart from horizontal one would also then need a bund - thus increasing its footprint.
The volume of the bund ( 110% of storage volume ) is the same irrespective of the storage volume being in a vertical tank or horizontal tank.
The tanks I'm looking at (2500 EHB horizontal and EVB vertical from https://www.envirostoreuk.com/tank-range/bunded-tanks/) are both fully bunded.
The horizontal one does have a slightly smaller footprint (2.50m2 vs 2.64m2) but occupies a considerably bigger overall area (3.41m2 vs 2.64m2) so I'm not sure that's much of an advantage. In fact, OFTEC say the base should extend 300mm beyond all sides of the tank, which might imply that the horizontal one would actually need a considerably larger base even though its footprint is a bit smaller.
The horizontal tank is less than 4 inches narrower, but nearly 2 feet longer. Obviously if you simply couldn't squeeze in those few inches of width but had plenty of room the other way then the horizontal would be the only option, but that's likely to be a tiny proportion of cases. That made me wonder if there's some other advantage of the horizontal that I'm missing, otherwise it seems they would be fairly pointless in most circumstances.
The horizontal one does have a slightly smaller footprint (2.50m2 vs 2.64m2) but occupies a considerably bigger overall area (3.41m2 vs 2.64m2) so I'm not sure that's much of an advantage. In fact, OFTEC say the base should extend 300mm beyond all sides of the tank, which might imply that the horizontal one would actually need a considerably larger base even though its footprint is a bit smaller.
The horizontal tank is less than 4 inches narrower, but nearly 2 feet longer. Obviously if you simply couldn't squeeze in those few inches of width but had plenty of room the other way then the horizontal would be the only option, but that's likely to be a tiny proportion of cases. That made me wonder if there's some other advantage of the horizontal that I'm missing, otherwise it seems they would be fairly pointless in most circumstances.
Eh? A bund makes the footprint bigger. Whether it’s vertical or horizontal so horizontal will always be bigger footprint than vertical! Bund or not!
True where the bund is a second skin to the tank.
But for a "tradditional" bund ( an oil proof and empty "pond" under the tank ) the foot print area A is determined by stored volume V and depth of bund D
A = V / D
How resistant to attack with malicious penetration are tanks with integral bund ? Risk assessment ?