Ask the Architect

Can I overload my balcony?


Q. I live in an apartment building with balconies, and wonder if you can tell me if there’s any way to know how many people I can have on my balcony at one time. This is the first time I’m having family and friends over for a party, and during the holidays I want to be sure they’ll be safe. Also, the railings have spaces between them, and I’m very concerned about the children who will be at the party. Is there a way to know whether I should restrict the balcony to adults, or just not use it at all? What’s the rule of thumb?

A. Good question! The answer requires a number of other questions to be asked and answered to determine how concerned you should be about safety. Consider that newer buildings were constructed with more stringent requirements, while older buildings may have maintenance issues — especially buildings nearer to the ocean — and may not have been repaired for decades. So age and location need to be known.
If you know that your building has been well maintained, age may not be as much of a concern. Other than unusual items like cars and swimming pools, one of the heaviest things that buildings are designed for is paper, in filing cabinets and bookshelves, so libraries need to be extra strong to hold such extreme loads as large racks, shelves and stacks of books and papers. The required load design for balconies is the same as libraries: 100 pounds per square foot.
Balconies have to not only hold the weight of people, but also carry their own weight, and heavy snow or ice, combined with high winds, without buckling. Typically, people gathering on a balcony should be similar to people gathering in the living room inside, and it’s rare to see people packed together in such a limited space without breathing room. You should use common sense, and social distancing would mean that you could limit people to being within a foot or so apart if you choose.
Again, it’s rare to see people jammed into such a tight space, but that can happen if everyone rushes out to see something going on outside, like a fireworks display, for example. The safety factor of 100 pounds per square foot will generally hold, but only if the other maintenance conditions are met.

As for the balcony railing, the maximum vertical or horizontal baluster spacing, or rail opening, is 4 inches, and for good reason: Children’s heads, from birth, are the largest part of their bodies, and larger than 4 inches in diameter. As they grow, their bodies catch up, proportionately. Although their bodies may squeeze through the space between railings, their heads generally won’t. A child should never be on a balcony without a responsible adult, but it does happen, and the rail space will at least protect a child from a fall. Happy holidays!

© 2021 Monte Leeper. Readers are encouraged to send questions to, with “Herald question” in the subject line, or to Herald Homes, 2 Endo Blvd., Garden City, NY 11530, Attn: Monte Leeper, architect.