Commercial HVAC Equipment

Why facility owners should consider a building envelope retrofit

Thursday, April 20 2017 3:55 PM
By Jon Goering

More than five million commercial buildings exist in the U.S., and they consume 40 percent of our nation’s energy.

More than five million commercial buildings exist in the U.S., according to a 2012 survey conducted by the U.S. Energy Information Administration.

These buildings consume 40 percent of our nation’s energy. And their average age? Fifty years (49.07 to be exact).

Understandably, these factors and others have led to today’s push for energy conservation in commercial buildings. One way to do that is by making improvements to building exteriors, known as an envelope retrofit. 

In this post, we’ll discuss the specifics of commercial building retrofits, how to determine if your building is a candidate, the building types where retrofits can have a significant impact, and retrofit funding options.

The Envelope

Those in the commercial building arena refer to the primary thermal barrier between the building’s interior and its exterior as the “envelope,” comprising walls, windows, roofs, and floors. These components can be made of metal, wood, stone, glass, even fabric, and they play a key role in determining levels of comfort, natural lighting, ventilation, and how much energy is needed to heat and cool a building.

As a building ages, its external components degrade, leading to poor energy efficiency and decreased occupant comfort, not to mention reduced equipment life and a decline in property value. Therefore, proactive owners must decide whether to demolish and build a new facility or retrofit their existing one.

Generally, retrofitting a building envelope costs less than constructing a new building. In fact, the trend has shifted from new construction to retrofits, comprising 61 percent of today’s construction projects, according to McGraw-Hill.

Naturally, a building that minimizes the loss of air flowing in and out through gaps in its barrier operates more efficiently. And that’s important, considering HVAC and lighting make up three-fourths of the energy use in commercial buildings. Air sealing – the restriction of air passing through the building envelope – can reduce the need for heating by 20 to 30 percent.

Fortunately, envelope materials and technologies have improved over the years, and numerous methods exist for retrofits. For example, a building owner may replace a façade, add exterior installation, update or replace windows and doors, and repair or replace roofs or floors. Other options for roofs and windows include adding reflective surfaces or low-e coatings to reduce energy consumption.

Before undertaking a building retrofit, however, you should consider these questions:

  1. What is the condition of my building? Is it structurally sound?
  2. Do upgrades need to be made to meet local building codes?
  3. Does my building contain hazardous materials such as asbestos and lead paint that need to be removed prior to work being performed?
  4. How will the project affect the occupants in my building?

If you determine that a building envelope retrofit should be conducted, your next move is to create a plan outlining the steps you intend to take.

Your plan should begin with an energy audit to determine if your building’s HVAC, lighting, and water systems are operating efficiently. Audits also can uncover other areas where energy improvements can be made such as replacing dirty filters, adjusting dampers, repairing wiring, enabling sensors, and repairing water leaks. In addition, study utility bills over two years to see if your building has increased its energy consumption.

Next, determine if your building is leaky or tight. Examine the building envelope to identify leaky windows, gaps where vents and pipes enter the structure, and areas where moisture has seeped in. Consider hiring a professional contractor specializing in this procedure as they have been trained to perform this work and can better identify potential problem areas.


HVAC and lighting make up three-fourths of the energy use in commercial buildings.

(Graphic courtesy of the Trane Company.) 

The Candidates

While many types of buildings can benefit from an envelope retrofit, some of the more popular ones include hospitals, high-rise buildings, and buildings being renovated for new use.

Hospitals are a good candidate because of the numerous legal criteria they must meet related to patient care and the amount of energy they use. Poor indoor air quality and temperatures too high or too low negatively impact patients and staff alike, placing enormous pressure on ventilation systems. Along with an envelope retrofit, hospitals also should consider updating their HVAC and lighting systems.

Large commercial buildings located in densely populated metropolitan areas make good candidates for retrofits due to the opportunities for improving energy efficiency and reducing noise. Many of these buildings were built 30 to 40 years ago when the materials for exterior coverings were far inferior. Additionally, the glass in older buildings often does little to reduce noise pollution from the outside and provides poor thermal protection. As a result, occupants suffer, and energy performance decreases.

Envelope retrofits to older buildings – historical ones in particular – make sense due to their connection to the past and place in the community. Generally, these types of retrofits adapt a building to meet a new purpose and are not to preserve or restore. An example of this is when the owners of old school buildings convert the structures to living spaces.


Many building owners understand and appreciate the importance of reducing their energy consumption from financial and environmental sustainability standpoints. The cost to do so, however, often acts as a barrier. Extensive capital costs can be overcome by utilizing any number of financial tools available today and through the energy savings realized by a building retrofit.

Some options include:

  • Commercial loans
  • Government supported low-interest loans
  • Performance contracts
  • Utility rebates
  • Tax incentives

Building owners also should consider as a resource the U.S. Department of Energy’s Advanced Energy Retrofit Guides. These documents provide building owners and others in the design-build arena with practical advice for energy-improvement projects from start to finish. Free to download, they address specific building types including offices, healthcare, K-12, and retail.

What makes these guides so useful is that they utilize expert advice in those specific markets to outline proven, effective retrofit practices at any stage of the process. The result will be energy savings far into the future.

Click here to see the Advanced Energy Retrofit Guides website.


Many building owners consistently look for ways to keep their facilities operating at optimum efficiency. Considering the average age of buildings in the U.S., however, doing so presents many unique challenges.

A building envelope retrofit is one way to effectively improve energy performance without the cost of building a new facility. Hospitals, office buildings, and renovations for new uses are all examples where a retrofit can have the most impact. And with a variety of options available today for financing a building project, doing so has become even more feasible.

Does your building consume too much energy? Has your utility spending steadily increased over the years? Is comfort an issue in your building? For more information, please email Jonathon Goering by clicking here or call 316-265-9655.

Knipp Services works with commercial and industrial building owners to identify solutions to reduce downtime and increase building efficiency. We provide services that enable building owners to have a high-performance building. “Making Buildings Better” sums up the mission statement of Knipp Services.


Facility Executive

American Council for an Energy-Efficient Economy

SMR Research

Whole Building Design Guide

U.S. Department of Energy


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