Modernizing an old house comes with challenges, and updating heating systems in a historic house is one of the most delicate. Homeowners want better indoor comfort products, but not at the expense of the architectural charm that makes these homes unique.

Opting for a custom HVAC system for an old house can help balance the past with the present. Performance without disruption is the approach we like! With thoughtful planning and the right technology, you can replace outdated heating and cooling systems while preserving the details that make a space special.

Old Houses Need Special Attention

Older homes weren’t built with central air conditioning in mind. Many lack ductwork altogether, and space for new equipment can be tight or oddly shaped.

On top of that, thick plaster walls, ornate woodwork, and original finishes are difficult (and expensive!) to repair if disturbed. That’s why replacing a heating and/or central air system in an older house calls for a much different approach than in newer builds.

Custom heat and air solutions offer flexibility. Smaller air handlers, mini-duct systems, and ductless mini-split heat pump options are easier to fit into tight spaces without disturbing walls or ceilings.

Some systems, like the Unico System, are designed specifically to provide modern comfort in homes with limited space for traditional ductwork.

Plan Ahead for the Best Results

HVAC retrofits often come later in the renovation process; however, starting earlier helps avoid costly workarounds or delays.

"When planning a retrofit or renovation, it's essential to consider your HVAC requirements early in the design process," shares Marc Mascarello, Head of Design at Invi Air. "If you are considering upgrading or modifying your HVAC system or changing the look of your diffusers to something more sleek and contemporary, these decisions should be considered as early in the process as possible."

He stresses the importance of letting all your contractors collaborate during the process. "Planning ahead and coordinating all the relevant trades with your interior design will ensure that your comfort and design options are not compromised by time, budget, or spatial limitations, and you will have the best results."

Working with an HVAC contractor who has experience with historic properties can also make a major difference. They’ll understand how to balance air sealing, ventilation, and insulation upgrades while keeping original materials intact. (Plus, stay in touch with annual inspections, and they'll be able to help with preventative maintenance, too.)

A slate roof made of composite shingles; copper detailing.
Updating historic homes can also involve using modern roofing systems. Credit: Brava Roof Tile

Custom Diffusers Make a Subtle Impact

A big part of keeping an older home’s charm is avoiding modern features that look out of place. Standard HVAC vents and bulky grills can interrupt the visual flow of a room. That’s why small touches, like custom air diffusers, can make such a difference without affecting the integrity.

“In residential design, every detail matters to create a home that feels comfortable and is functional to the owner,” notes Mascarello. “[Air] diffusers offer seamless integration into any living space, combining innovative materials with revolutionary design to ensure optimal air circulation without compromising aesthetics."

Describing how his company's system uniquely helps older and historic homes, he adds, "Being frameless and flush-mounted, Invi Air’s diffusers seamlessly integrate into walls and ceilings, eliminating unsightly vents that disrupt the charm of historic buildings and retrofit projects. Our diffusers are the perfect choice for historic homeowners who want a sleek, clean look while enjoying improved IAQ and a quieter, more comfortable home."

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Common Solutions That Work for Historic Homes

Some HVAC options fit better than others in older homes. The right system often depends on layout, budget, and long-term energy goals. An HVAC contractor familiar with custom services for historic properties can help you find the best fit.

Here are a few heating & cooling systems and techniques worth considering as you work with experts for your unique system layout:

  • Mini-split heat pumps: No ducts required, making them great for rooms that need independent temperature control.
  • High-velocity systems: Small, flexible air ducts that can be snaked through walls, floors, or ceilings with minimal damage.
  • Water-to-air systems: Often used in homes with radiant or boiler heat, this system uses existing infrastructure to distribute air.
  • Custom diffusers: Frameless and flush-mounted, they eliminate bulky grills and maintain design flow.
  • Zoned heating and cooling: Offers energy savings by controlling comfort in specific areas, rather than the whole house at once.

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FAQ

Can I install central air in a historic home without damaging the structure?

Yes, in some cases a mini-duct or high-velocity system only requires small openings, making it possible to preserving much of the original architecture. A mini-split heat pump system may also be a good solution when ductwork isn’t feasible.

What’s the benefit of custom HVAC solutions for old houses versus off-the-shelf systems?

Custom solutions allow you to tailor the system to your home's layout and aesthetic. This can mean quieter performance, better energy savings, and a system that doesn’t disrupt the home's character. Off-the-shelf systems often require larger ductwork or vents that may not suit older construction.