Heating and Air Conditioning for a Home Addition

Updated: July 2023
Heating and Air Conditioning for a Home Addition

If you’ve decided to expand your home, a separate ductless or ducted mini- or multi-split system can heat and cool the new space without modifying your existing HVAC system or spending money on new ductwork. 


Licensed HVAC contractors size all heating and air-conditioning systems to heat and cool a defined space under specific conditions including the number of windows and doors, level of insulation, and local design temperature. Your system was sized to keep your home comfortable as designed and won’t be able to sufficiently condition the expansion. Adding ductwork in the new space and connecting to the existing trunk isn't practical as the system's not powerful enough. Replacing the whole system would be costly and you wouldn't have the same control over your comfort in the new space.


Zoned comfort

Our ductless and ducted mini- and multi-split systems are Zoned Comfort Solutions® with intuitive controls and an outdoor unit connected to up to eight indoor units via refrigerant lines. Each indoor unit serves a designated comfort zone in the home. Your ductless indoor unit options include wall-mounted, floor-mounted and ceiling cassette styles. They're great options for the new addition because they're simpler to install than ducted units and they function as a stand-alone system not connected to the system in the rest of your home. If you’re into high ceilings, you can have them in your expanded livable space with a ductless system.


Zoned Comfort Solutions provide designated energy-efficient heating and air conditioning for your new comfort zone. The outdoor unit’s INVERTER-driven compressor modulates the system’s capacity to meet the zone’s demand for heating and air conditioning regardless of the shifting heat load caused by occupancy, activities in the room, or the sun moving over the home during the day. With this approach, the system maintains your preferred temperature, or set point, for the zone while using minimal energy. Your addition might be an extra bedroom, an exercise room, a home office, or even a group of rooms with their own separate requirements, but each zone can have an individual set point. Also, if you use the additional space infrequently, you can save money and energy by turning off conditioning until you’re ready to use the zone again.  


More zones, less disruption

Amy and Rodney Lumpkin decided to make a 1,000-square-foot addition to their 3,000-square-foot home in Limerick, Pennsylvania. The addition would include two new bedrooms, a bathroom and more livable space. The family’s existing HVAC system didn’t have enough capacity to keep the new spaces comfortable.


With the couple and their five children living in the home during the addition’s construction, the Lumpkins wanted to keep disruptions to a minimum. Installing Zoned Comfort Solutions from Mitsubishi Electric only required one day of major work and they didn’t have to change their existing system. They mixed and matched ducted and ductless indoor units and resealed and repurposed old ducts.


Mitsubishi Electric Trane has ducted and ductless heat pumps and air conditioners with indoor unit styles for every home and addition. When you’re ready to expand your livable space, contact one of our Diamond Contractors to get started.

Home addition
Home renovation
Ceiling cassette
Product Applications
Residential Applications