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What Size Furnace Do I Need?


When purchasing a new furnace for your Cincinnati area home, size certainly matters. Your new furnace needs to be the appropriate size for your living area to maximize comfort. Installing a heating unit that is too small or too large cannot heat your home efficiently, causing comfort problems and increasing heating costs.

Before purchasing a new furnace, your HVAC technician will calculate the appropriate size of equipment that you need. In the latest blog from Nelson Comfort, we’ll discuss some things that an HVAC professional will look for before recommending a furnace size for your home.

What Factors Determine the Size Furnace or Heating System You Need?

Square Footage Of Your Home

Measurements will be taken of all the rooms within your home. Unconditioned areas, such as garages and attics, will not be included. If rooms in your home have high or vaulted ceilings, the ceiling height will also be measured. This will determine if your home needs a smaller or larger furnace in terms of heat output.


The U.S. Department of Agriculture assigns zone numbers to each region, indicating the climate and temperature variations of each area. Cincinnati homes are zone 4. The climate zone is considered in determining the capacity of a new gas furnace to meet your home’s needs.

Home Insulation and Construction

The level of insulation in a home, as well as the construction materials used, will also help to determine the right size furnace for the home. More heat loss occurs in homes built using certain materials or with low levels of insulation. Because of this, the size of your new furnace must be able to make up for this loss while still providing enough heat to keep you safe and comfortable during the winter months.

Furnace Efficiency

More efficient gas furnaces produce more heating compared to their less efficient counterparts. If you have decided to purchase a high-efficiency furnace model, you may be able to utilize a smaller capacity model. When using a low-efficiency furnace, on the other hand, a larger capacity model may be required to gain the same amount of heating.

Contact the Heating Professionals at Nelson Comfort Today

There are many calculators online to assist you with furnace sizing, but beware that they may not accurately factor in the particulars of your home. The best way to find out the right size furnace for your home is to consult a heating professional to perform accurate sizing calculations specific to your living area.

For assistance sizing your new furnace, call the heating experts at Nelson Comfort today. Our HVAC professionals are backed by years of experience and will provide you with the information that you need in order to make an educated and informed decision.Contact us today to get started.

About The Author


Dan Detmer

Dan Detmer is the owner of Nelson Comfort. Dan was born into the heating and cooling industry, coming from a family of well respected HVAC contractors in Dayton, Ohio. After working in the family business, Dan decided to work for a local HVAC wholesale business helping local contractors grow their business. When he felt his heart moving him back into the residential and light commercial business, Dan joined the Mortimer Heating & Cooling team in Cincinnati, where he had called home and become part of the community for several years. After a short period of time Dan purchased the company and created what is today, Nelson Comfort. Today he operates a company based on integrity, honesty, and stellar customer service. If you have any questions feel free to tweet (at sign) NelsonComfort and we will get right back with you!

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