Latex balloon sizes, float time and when to inflate
Latex balloon sizes, float time and when to inflate
Balloon packs are described by a number of inches and a count, and both are more informative than they look. Here is what they mean in practice.
What the inch figure describes
A 12-inch balloon is twelve inches across when inflated to its intended size — not the size of the deflated balloon, and not a maximum. Under-inflating a 12-inch balloon to nine inches makes it pear-shaped; over-inflating it makes it translucent, thin-walled and short-lived.
Twelve inches is the general-purpose party size. Smaller sizes exist mainly as filler in garlands. Larger sizes are statement pieces and need proportionally more gas.
Float time, honestly
A standard 12-inch latex balloon filled with helium floats for somewhere in the region of half a day to a day, depending on temperature, humidity and how well it was tied. Latex is porous and helium is a small molecule, so it escapes steadily through the balloon wall.
That is the single most useful fact for planning. Inflating latex with helium the night before a party is how people end up with a floor full of balloons at three in the afternoon.
Treatments that extend float
Liquid balloon sealants coat the inside of a latex balloon and slow the leak considerably, often to several days. They are worth using for anything that must float for longer than an evening.
Foil balloons are a different material entirely and hold helium for days without treatment, which is why numbers and letters are usually foil.
Air-filled decorations are the opposite
Air does not escape latex nearly as fast as helium. An air-filled garland, arch or column built the day before will still look right the next evening, and will often last several days.
This flips the usual planning advice. Anything that floats should be done at the last possible moment; anything that does not float should be built in advance, when there is time and nobody is waiting.
Temperature moves balloons around
Gas expands with heat. A balloon inflated in a cool room and then moved into a warm one grows, and one taken outside on a cold evening shrinks and looks under-filled.
Two practical consequences: do not inflate to absolute maximum indoors if the decorations are going outside into the sun, and do not panic when balloons look deflated in the cold — they usually recover.
Direct sunlight on dark latex is a particular problem, because it heats the gas fastest and degrades the latex at the same time.
Tying, weighting and ribbon
Most float failures are actually tie failures. A tie that includes a small twist before the knot holds far better than a knot alone.
Weights matter more than people expect: an untethered helium balloon indoors is on the ceiling permanently, and a cluster without enough weight drags across the table. Match weight to the number of balloons rather than using one weight for everything.
Storage before the party
Uninflated latex balloons keep well in a cool, dark, dry place. Heat and light degrade latex in the packet, which is why a bag left on a sunny windowsill for a month produces balloons that split at inflation.
Practical checks before ordering
- Check the inch size as well as the count.
- Plan helium inflation for the day of the event, not the night before.
- Build air-filled garlands and arches in advance.
- Add sealant if latex must float longer than an evening.
- Order weights sized to the clusters you are making.
- Store unused packs cool, dark and dry.
Where this sits in the shop
Everything discussed above comes back to one part of the shop: Balloons, which currently holds 1 listing. The whole of it is picked and packed at Party Plan-It, 8414 5th Ave, Brooklyn, NY, during Tue–Sat 10:30am–7pm, Sun 10:30am–3:30pm, closed Monday — so anything written here can be checked by phoning the counter on ((718) 836-3701.
From our shelves
What we get asked about this
Do you ship outside the United States?
Not at present. We ship to US addresses only, including Alaska, Hawaii and territories the carrier serves.
Can I pick my order up at the shop?
Web orders are shipped, not held for collection. If you want to buy in person, come to 8414 5th Ave, Brooklyn, NY 11209, United States during opening hours (Tuesday–Saturday 10:30–19:00 · Sunday 10:30–15:30 · Closed Monday) and buy across the counter instead.
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Ordering from Party Plan-It
Orders of $49.00 or more ship free anywhere in the United States, and a flat $5.99 covers everything below that. Handling takes 1–2 business days and carrier transit is normally 3–7 business days. Unused items can go back within 30 days, and if the mistake was ours we pay the return postage.
Questions about anything above go to [email protected], answered within 1 business day, or call (718) 836-3701. Full detail is on the Shipping Policy and Refund and Returns pages.