Natural Ventilation feels comfortable at times and sometimes it does not.  Being a true believer in green would mean that you are not open to mechanical ventilation, based on the use of outside energy sources.  It is not overly difficult to create a heat stack in a “simple” building and move hot air upwards naturally out of a building.  The wind can blow through the building sucking the hot air out.  The science of thermal buoyancy can also be used creating what is called stack ventilation.

Image By:  http://www.greenandnaturalbuilding.com/IndoorAirQuality/?page_id=10

Image By: http://www.greenandnaturalbuilding.com/IndoorAirQuality/?page_id=10

A cool tower is a third concept using wind and buoyancy and fans to provide airflow.

Basic Cool Tower

Basic Cool Tower

So, how do we make this happen?  Simulation software that is easy, fast, accurate and is not heavily reliant on CAD would be seem to be one of the answers.  Simulation software is the key to making modeling of buildings easier for architects and mechanical engineers.  According to the blog Another Fine Mesh, written by The Congress on the Future of Engineering Software, 1 out of 6 engineers already use some type of simulation in the design process.

Another answer is utilizing product designs that can control the opening and windows and vents.

A recent Construction Specifier magazine article, Natural Ventilation, page 14, speaks to the pros and cons of integrated ventilator and actuated window systems to control natural ventilation inside a building.

My approach is always to foster early conversation with the mechanical engineers about the design concepts, owner’s requirement and about modeling of the natural airflow.