HVAC for Home Remodels: What Homeowners Should Know

Thinking about renovating your home or adding a new room? Most homeowners focus on paint colors, flooring, and windows—but often overlook the role of their HVAC system. Heating, ventilation, and air conditioning are essential for keeping your new space comfortable throughout the year.

Failing to plan your HVAC system during a renovation can result in uneven temperatures, drafty spots, or even high energy bills. By designing an efficient heating and cooling solution from the start, you can enjoy a cozy, energy-smart home without surprises.

What to Consider

Every remodel project is unique, with its own specific HVAC challenges. Understanding these challenges is the first step toward a successful climate control strategy.

• Finished Basements: A basement is inherently susceptible to high humidity and moisture. Simply extending your existing ducted system may not be enough to handle this unique environment. You need a solution that can effectively control moisture.

• Garage Conversions: This is a classic example of a complicated remodel. A garage is an uninsulated shell with no existing ductwork. It's often difficult to run new ductwork into a garage, making a dedicated, independent solution a necessity.

• Attic Conversions: Attics are notorious for extreme temperature swings, with significant heat gain in the summer and heat loss in the winter. Overburdening your existing central system to cool or heat this space can lead to inconsistent temperatures throughout the entire house.

• New Room Additions: Adding a new room increases the total square footage of your home. Your existing HVAC system may not be able to accommodate the indoor comfort required of this newly added space. A common and costly mistake is to "steal" conditioned air from other rooms by extending ductwork, which creates imbalances and temperature inconsistencies.

Regional Considerations

The North American climate varies widely, and HVAC solutions must be tailored to the specific region.

• Hot & Humid Climates: In regions like the Southeastern U.S., the primary challenge is high humidity. In these climates we recommend systems with variable-speed, inverter compressors because they operate at low speeds for long cycles, which is very effective in removing moisture from the air.

• Cold & Very-Cold Climates: While gas furnaces have been traditional, modern cold-climate air-source heat pumps are now designed to provide efficient heating. Some models are even designed to maintain comfort in sub-zero temperatures. For those who live in cold climates who already use a gas furnace, a dual-fuel system that pairs a heat pump with a gas furnace is a robust solution.

• Dry & Mixed-Dry Climates: The focus in these arid regions is on effective cooling and moisture supplementation. Options include evaporative coolers or central systems with integrated whole-home humidifiers to combat low humidity.

Extend Ductwork or Go Ductless?

There are three main options to address indoor comfort in a remodel.

1. Extending ductwork can be effective if your current system has sufficient capacity for the new living space.
2. Upgrading your current system or adding a zoned unit to account for the additional load calculation.
3. Add a ductless mini-split, which is ideal for additions like sunrooms, basements, or garages.

All options can deliver comfort, but the right choice depends on your home’s layout and the results of the load calculation.

HVAC sizing and the load calculation

An important step in a home remodel is to hire a qualified HVAC professional early in the planning process. An experienced HVAC contractor should perform a detailed Manual J load calculation, which considers dozens of variables, including your climate, insulation, windows, and square footage.

Studies by the National Renewable Energy Laboratory (NREL) show that skipping this step often results in systems that are either oversized or undersized, increasing energy costs (nrel.gov).

Modern HVAC Solutions for Remodels

Whether you’re extending ductwork, adding a zoned HVAC system, or installing ductless mini-splits, the right approach makes all the difference in your home’s comfort and performance.

*Efficiency varies based on the HVAC equipment’s energy efficiency ratings.

Resting Easy

The success of any home remodel is inextricably linked to a well-planned HVAC strategy.

By understanding the unique challenges of each project, considering regional climate factors, and exploring modern solutions, you can ensure that your investment yields a comfortable, efficient, and lasting living space.

It is highly recommended to consult a qualified HVAC professional early in the planning process to perform a proper load calculation and design a tailored HVAC solution.