Diagram of AC System in Historic Home, Credit: Pinterest
They don’t call climate change “Global warming” for nothing. As the average temperature of the planet increases each year, the need for air-conditioning becomes greater each year. The fact that creating the energy to create this air-condition accelerates the global climate problem creates a viscous cycle. Still, as U.S. summers grow increasingly intense, homeowners with older houses face the challenge of maintaining comfortable indoor temperatures. While charm and character define these dwellings, their original construction often lacks modern climate control. Retrofitting for air conditioning is no longer seen as a luxury, but as a necessity.
Installing Condenser Example
Traditional central air systems, while effective, can be difficult and expensive to install in older homes. Bulky ductwork, a crucial component, may require extensive and disruptive renovations, potentially compromising historic buildings’ architectural integrity. Fortunately, this is where newer technologies can offer better alternative solutions.
Diagram of High Velocity Mini Duct System, Credit: Alhudapk
High-Velocity Mini-Duct Systems: These systems utilize narrow, flexible ducts that can be threaded through existing walls and ceilings, minimizing the need for major structural changes. The smaller duct size also allows for a more discreet installation, preserving the aesthetic appeal of older homes. High-velocity systems deliver conditioned air at a higher pressure, resulting in rapid cooling and even temperature distribution. While potentially pricier upfront, the reduced disruption and efficient performance make them a compelling option. The vents are small round disks, rather than large metal grates.
Diagram of Mini Split System, Credit: MitsubishiComfort
Ductless Mini-Split Systems: Offering even greater flexibility, mini-split systems consist of an outdoor compressor and one or more indoor air handlers connected by refrigerant lines. These systems eliminate the need for ductwork altogether, making them ideal for homes where duct installation is impractical or impossible. Each indoor unit can be individually controlled, allowing for zoned cooling and energy savings. Modern mini-splits are also increasingly energy-efficient and quiet, making them a popular choice for older homes. The visible indoor units have also become more aesthetically pleasing over time, and can be placed in less noticeable locations, like the ceiling, or disguised behind flat wall panels upon which art can be hung.
There are many practical considerations for designing and sizing the right system to retrofit an older home with air conditioning.
Spray Foam Insulation Example, Credit: OldHouseGuy
Insulation: Before installing any AC system, ensure the building is adequately insulated. Proper insulation in the attic, walls, and floors will significantly reduce heat gain and improve the efficiency of your cooling system.
Single vs Double Pane Windows, Credit: Window Whirl
Window Efficiency: Older windows are often single-pane and leaky. Replacing them with energy-efficient double or triple-pane windows can drastically reduce heat transfer and improve overall comfort.
Electrical Updates Example
Electrical Capacity: Older electrical systems may require upgrades to handle the increased load of air conditioning. Consult with a qualified electrician to ensure your wiring is adequate and safe and with the local utility to confirm that the additional electrical capacity is available to your property.
Moisture Barrier Example, Credit: The Green Cocoon
Moisture Control: In humid climates, proper moisture control is essential to prevent mold growth and maintain indoor air quality. Including dehumidification features in your chosen AC system or supplemental dehumidifiers may be very beneficial.
A4 Architecture Principal Ross Cann
Professional Assessment: Due to the unique challenges of older homes, it’s crucial to consult with a qualified HVAC and architectural professionals who has experience in retrofitting these types of structures. They can assess your building’s specific needs and recommend the most appropriate, efficient, and cost-effective solutions.
Diagram of AC System in Historic Home, Credit: UnicoSystem
With careful planning and the right technology, homeowners can effectively adapt the charms of older homes to the realities of a warming climate, ensuring comfort and preserving the character of their historic dwellings. A4 Architecture is experienced in these tasks and is pleased to help building owners in Rhode Island and adjacent states help renovate the structures to not just be beautiful, but comfortable and energy efficient as well.
Ross Sinclair Cann, AIA, LEED AP, is an historian, author, educator and practicing architect living and working for A4 Architecture in Newport, Rhode Island. He studied Molecular biophysics at Yale, received an M.Phil in Architectural History from Cambridge University and earned a M.Arch in Architectural Design from Columbia University in New York.