Big Steps In Building: Make Natural Ventilation Mandatory


Hallandale, Florida's oceanfront is wall-to-wall condos; you can tell the ones built in the recent boom because they are generally huge stucco and glass monsters like the one on the left, interspersed with older, lower buildings that were just big enough to avoid being flattened. But more than size separates them.

The big building is a center-corridor design that is identical to what might be built in New York or Toronto. The corridor is air conditioned and cold. Outside it is in the mid 70's and the wind is blowing hard, maybe 20 knots off the water. We have all the windows and the patio door open. In the dining room it is stuffy and hot. In almost every other unit the patio doors are closed and the air conditioning is running.


The older building to the right does not have pressurized air conditioned corridors; it has an exterior walkway at each level serving the apartments.


The older building is slender, and the doors to the corridor have jalousie windows that crank open. The breeze can blow through the apartments and on a mid-winter day in Florida they do not need air conditioning. The building is designed with the climate in mind, in a pattern used in hot countries all over the world. There may well be air conditioning in every unit, but it is under the owner's control. It is all low-tech but also low-energy.


But in Florida density trumps energy efficiency. (dare I use that word trump? it is on every second unfinished building here.) It is hard to pack them in as tightly in a single-loaded building as it is in a double loaded one, and developers will naturally build as big as the zoning bylaws and the building code lets them.

Such densities can only be achieved by using energy, to pressurize and air condition the corridors and to air condition the apartments that are otherwise marginally habitable in the middle of February. To permit such designs to be built in this century, where the developer gets the sales and the owner is stuck with the operating costs, is unconscionable and wrong.

We are in a time-out right now thanks to the mortgage meltdown. Let's use it to re-write the building codes to ensure that every new apartment is designed so that natural cross-ventilation is a design requirement, as important as windows.


It isn't only in the South; in northern cities like New York, even the cheapest tenements were required by law to have natural light and ventilation to kitchens and bathrooms. Sometimes it might be little more than a slot, but those were the rules. Then the electric fan was accepted as a substitute. Lightwells and light slots disappeared as powered technology replaced windows.

It is time to bring the old rules back. Natural light and ventilation should be available to every room; the ones that make the smells should have as high a priority as any other.