How We Estimate the Right Size Furnace for Your Home

Every home has unique heating requirements, and when it comes to choosing a furnace, finding the right size for your home is essential. Today’s article tackles how HVAC companies make these estimations.

The Importance of Size

A properly-sized furnace ensures indoor comfort without forcing you to spend more on heating than you need to. Meanwhile, an improperly-sized furnace can lead to inconsistencies in indoor temperatures, unnecessary energy expenses and an inefficient unit that will continue to experience issues.

If you have an oversized furnace, you may notice that your living spaces are being heated unevenly. Your furnace is likely also turning on and off at a faster rate, placing additional strain on its inner components that will eventually lead to its premature failure. If you have an undersized furnace, on the other hand, it will have trouble keeping up during the coldest winter days, running nonstop and consuming much more energy than necessary. This will also cause it to wear out sooner.

Calculating Furnace Size

Home heating companies take several factors into consideration when estimating furnace sizes.

  • Square footage – How big is your home?

  • Heating factor – Where are you located? The five U.S. climate zones all have different British thermal unit (BTU) requirements. The farther a place is from the equator, the higher the required BTUs will be. We fall under Zone 3, which has a heating factor of 40 to 45 BTUs.

  • Insulation – How much insulation does your home have?

To calculate your home’s heating requirements, we multiply its square footage by the appropriate heating factor. If your home is well insulated, the lower BTU value is chosen. From there, we can select a furnace that corresponds to the value we came up with.

As one of the top heating and air conditioning companies in the area, Stone Heating and Air takes pride in offering only the best in HVAC products and services. By partnering with brands that work just as hard as we do, we bring you durability and the highest quality standards in the market today—all dedicated to your comfort.

Call us today at (541) 855-5521 or fill out our contact form to request an appointment.

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We had our AC go out on one of the hottest days of the year. We called as soon as they opened and they came out so quickly and offered us some loaner units to keep our babies and animals cool in the meantime. Matt was so helpful and fixed the problem quickly. He went above and beyond to help us and we will be using Stone Heating and Air to replace our unit when it’s time. They’ll be our first call in the future!

Elizabeth T.

Matt's response was extremely quick, he was very professional and friendly. He explained everything in detail and was very knowledgeable. He had my unit up and running within no time! I highly recommend calling stone heating and air. I will be signing up for the yearly service plan with them!!

Tim S.

I had a wonderful experience to hangout with this superior crewmen who came to install a new HVAC system at my house. To see these professional guys were at work with their best, I would recommend to anyone to do business with this wonderful company! Best regards

Bryan H.

I’ve used Stone Heat and Air for several projects and every time they have preformed beyond my expectations. I would highly recommend them for any of your HVAC needs.

Matthew V.S.

Excellent Service I could not have been more happy with the service, quality and honesty that I received from Stone Heating and Air. I will refer this HVAC company to all of my friends.

Gene S

Great Service, knowledgeable service technician This was for our guest house heater. I was very happy with the service provided. They were on time, polite and clean. They inspected the Monitor heater and then proceeded to clean it and they were able to fix that. Will definitely use for jobs in the future

Amanda S

Maintenance Great service, and great price

Mike J.

Great Company Dave was fantastic. He is very knowledgeable about the system and his cleaning job was incredible. He was able to explain everything that he was doing and make it make sense for general homeowner. Good Job guys!

Brian F

Excellent service! Excellent service! Knowledgeable staff! I was very impressed with the responsiveness and knowledge of your team. Shortly after 1 called for an appointment, Dave and Gino did a thorough inspection of my system and explained all of the areas that needed repair or replacement. They gave me short and long-term options and the benefits of both. HVAC is not something I know a lot about so I had appreciated their patience. Overall, it was a great experience! 5 STARS!! Highly recommend Stone Heating and Air!

John L

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