Minneapolis is lined with high-rise buildings and large structures throughout the city. Whether a condo complex, hotel, or multi-floor commercial space, all buildings with stairwells are required to meet U.S. Commercial Building Code standards for stairwell pressurization. Stairwells — the primary means of escape during a fire — must be designed so the stairwell pressure is higher than that of the rest of the building.

Why Is Stairwell Pressurization Important?

Stairwell pressurization is important for the following reasons:


●        The stairwell pressurization serves several purposes.

●        Inhibit migration of smoke to stairwells, areas of refuge, elevator shafts, or similar areas.

●        Maintain a tenable environment in areas of refuge and means of egress during the time required for evacuation.

●        Facilitate the fire and rescue operation by improving visibility in the building for the firefighting crew.

●        Protect life and reduce damage to property.


An electrical fire in a high-rise resort can become engulfed in flames and clouded with smoke due to lack of proper pressurization. During a fire, occupants evacuate using the nearest stairwell or exit. The heavy steel doors to the stairwell, designed to minimize smoke leakage, will open as occupants make their way down to safety.


The question, however, is what happens to the smoke in the hallway when evacuees or fire-rescue teams open the side doors. If the stairwell is of equal or lesser pressure than the hallway, the billowing black smoke will quickly fill the stairwell, making the safe exit for the hundreds of people on other floors more difficult.

How Does Stairwell Pressurization Work?

Stair pressurization creates a barrier to help control smoke movement in case of an emergency.


Professionals use special tools to measure and test stairwell pressure, accommodating for air leakage. Stairwells are fitted with specialized Stairwell Pressurization Systems or Stairwell Pressurization Fans to make sure the stairwell pressure is greater than the interior building. The higher pressure in the stairwell forces the smoke back into the lesser pressurized hallway, allowing the escape route to be free of smoke.

Does My Building's Stairwell Need to Be Pressurized?

Yes, not only is stairwell pressurization an important fire safety measure, but it is also the law. LKPB engineers stay current with pressurization regulations relevant to IBC (International Building Code) and Minnesota state codes.


We can offer a comprehensive stair pressurization analysis to determine what adjustments you need to make to reduce this dangerous safety hazard.

Engineering Services in Minneapolis, Minnesota

If you are looking for building design & engineering solutions in Minneapolis, MN, then contact LKPB Engineers. We offer a wide range of project management, design, and engineering services for commercial properties.


To schedule a consultation with an LKPB engineer, call us at 612-540-5000.