how much space do you want to fill?
Expect it to double in size... nearly double in height is a safe guesstimate for most. But with double area you must consider it's a lxw product, so .75x.75 is about 1/2 of a 1x1. so, a bit less than 3/4 your L and W dimension should be safe when it comes to area... height is easily measured unlike the area.
This is 100% about the space you want to fill or maybe a time constraint. So, 100% upto you what works best for your context.