Today’s buildings are far more sustainable than those of yesteryear, but new construction is not always the most eco-friendly option. Demolishing an old structure and erecting a new one involves considerable energy consumption and material waste. Adaptive reuse poses a unique solution, but it’s not without its challenges, either.
What Is Adaptive Reuse?
Adaptive reuse is the act of repurposing an existing building for a new use. Apartments built out of old offices or restaurants inhabiting old industrial spaces are common examples. Whatever the specifics, it’s an increasingly popular practice — office-to-apartment conversions have quadrupled since 2021 — and it presents several environmental benefits.
Reimagining a property instead of clearing it for new construction produces fewer process-related emissions. Similarly, it prevents material waste, as much of the original structure still stands after project completion. Urban expansion and its impact on surrounding ecosystems also slows as a result, as reuse reduces the need for additional land.
The population is growing, but the world only has so much space and so many resources. Given these constraints, adaptive reuse is a critical step forward, but firms embracing it must consider its unique energy efficiency challenges.
Energy Efficiency Challenges in Adaptive Reuse
While using an old structure instead of erecting a new one from scratch is generally preferable, it introduces energy efficiency concerns. Buildings’ ongoing operations account for 30% of global power consumption and 26% of related emissions. Those figures have declined in newer construction, but older properties don’t meet the same standards.
One of the biggest challenges is the inefficiency of outdated HVAC systems. The furnaces, air conditioning ducts, and other heating and cooling infrastructure of yesterday produce considerable power losses compared to modern alternatives. Adaptive reuse may also mean a once-industrial space must become residential, and the former’s HVAC may not be suited for the latter’s needs.
Similarly, the existing building’s insulation may be a concern. Many older options have less insulation than modern ones, and what they do have may have deteriorated over time. Consequently, it becomes difficult to maintain optimal indoor temperatures without losses that lead to excessive HVAC-related power consumption.
Firms may also face restrictions on the kinds of upgrades and additions they can implement. Apart from working within the confines of the property and its load-bearing walls, there are zoning codes and historic preservation laws to consider. These may limit how much teams can restructure or update a building.
Potential Solutions
Despite these challenges, adaptive reuse is still the most eco-friendly way forward in many cases. Construction companies tasked with repurposing older structures can account for the inherent energy efficiency obstacles in a few ways.
1. HVAC Retrofits
Replacing the old HVAC system is the most important step, as this is typically the most energy-intensive operation within the property. Simply retrofitting existing infrastructure with newer, more efficient alternatives can result in significant savings.
In some cases, teams will also need to replace pipes and vents, resulting in high costs. However, remodeling is more cost-effective than new construction or expansion. As a result, the expenses may even out in the end.
Applying additional insulation around vents and servicing parts of the system crews don’t replace will also help. Regardless of the specifics, these upgrades do not need to be extensive to be effective.
2. Renewable Energy
Similarly, adaptive reuse benefits heavily from on-site renewable power. Rooftop solar and similar structures provide two main advantages. First, they offer an emissions-free energy source, and second, they reduce the property’s reliance on the grid.
Poor HVAC and insulation efficiency are less of a concern if excess electricity does not result in higher emissions. Many old buildings rely on passive design to compensate for less effective ventilation and cooling, which makes them primed for renewables. Structures already capitalizing on the sun's position and being able to withstand outages can get more out of solar than others.
Freedom from the grid will help by offsetting ongoing costs. These financial gains can make up for higher electrical use.
3. New Building Envelopes
Construction teams can deal with insulation problems by erecting a new building envelope. Facades and other enveloping options are often not structurally integral, so they require minimal interference with the existing building but can provide room for additional insulation.
The envelope is where most energy losses occur, as it’s where the property meets the outside environment. Consequently, it offers some of the greatest potential for improvement. The nature of these structures also means teams can install a new one instead of redesigning the entire building.
Several envelope approaches can yield sustainability gains. Applying additional insulation between the facade and interior walls is the most obvious option, but using glass to create passive solar heating and cooling can also work.
4. Sealing, Glazing and Interior Insulation
Sometimes, historic designations or similar regulations may prevent large changes that would affect a property’s appearance. One way to work around this obstacle while improving insulation is to focus on sealing, glazing and interior padding.
Sealing cracks and gaps that have emerged over time won’t dramatically alter appearances but stops waste. Firms can also replace windows with similar-looking but newer alternatives. Multiglazing is one easy option, but gas-filled fenestration may be more impactful. Argon stops heat transfer 67% more effectively than air, so it’s preferable when budgets allow.
Insulating the interior instead of the envelope may be a viable course of action, too. Adding a layer of padding behind a new interior wall likely fits within many codes but provides the same benefits.
5. Smart Controls
Installing Internet of Things (IoT) systems can also help. Smart controls can adjust HVAC, water, lighting and other points of power consumption according to real-time needs to prevent waste. Because they require no structural changes, they’re also ideal for situations where larger renovation options are limited.
Smart thermostats and other HVAC technologies will produce the most significant savings. However, IoT lighting can also be beneficial. Combining multiple systems, when possible, is usually the best way forward, as it maximizes the resulting benefits.
IoT devices do consume some electricity themselves. However, these withdrawals are minimal compared to the amount they save in the larger system, so overall power consumption will still fall.
Get the Maximum Benefits Out of Adaptive Reuse
Adaptive reuse is an essential step forward to make the building and construction industry more sustainable. Still, its unique energy efficiency obstacles require attention. Once teams recognize these challenges and understand the relevant solutions, they can push this practice’s advantages as far as possible