I am not sure if there is an average size for balloon columns. It depends on the occasion, the venue and your budget. Sizes offered by professional balloon decorators range normally between 6 ft and 14 ft. How many balloons you need depends on the size of balloons you want to use...
5 inch balloons = 12 per foot
9 inch balloons = 8 per foot
11 inch balloons = 6 per foot
14 inch balloons = 4 per foot
16 inch balloons = 4 per foot
On our site, you'll find a step-by-step guide, including a list of all materials you need, for a 7 ft high balloon column and its base.
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