What Size Furnace Do I Need for My Boise Home?

If so, you might be wondering what size furnace you should get.

Here’s the thing, though: Only a licensed professional can answer this question after inspecting your home and current HVAC system. More specifically, a professional will need to perform a load calculation to find the correct size furnace for your home.

We know you probably have more questions, like:

  1. What is a load calculation?
  2. Why does furnace size matter?

We’ll answer these questions below. But first, we’ll give you a quick warning about “rule-of-thumb” sizing estimates.

Want a Boise professional to recommend a furnace size for your home? We can help!

Beware of rule-of-thumb size estimates

If you’ve looked online to find information about furnace size, you may have noticed some sources say the only factors you need to consider are the square footage of your home and the climate you live in.

The truth is, those are only two of many factors to consider. If you go with a furnace size recommendation based only on those factors, you will likely end up with an incorrectly-sized furnace, which leads to some serious issues (more on that below).

Beware of contractors who give you size estimates over the phone or only based on your home’s square footage. Ask the contractor to perform a load calculation to determine the right size furnace for your home.

Question #1: What is a load calculation?

load calculation is a complex analysis that takes into account several factors specific to your home. The purpose of this calculation is to help an HVAC technician correctly size your furnace.

What factors are considered in a load calculation?

A load calculation takes into account factors such as:

  • The orientation of your home (north-facing, east-facing, etc.)
  • The landscape and layout of your home
  • How many windows and doors your home has
  • The type of roofing on your house
  • The size of your home (square footage)
  • The insulation levels of your home
  • The materials your home is made of
  • And much more

As you can see from that list, a load calculation can get pretty complex (too complex for a homeowner to conduct without any tools). Luckily, licensed professionals have software that helps them with this calculation, which reduces human error and helps accurately determine what size furnace you need for your home.

Question #2: Why does furnace size matter?

Often we think that bigger is automatically better. However, when it comes to sizing a furnace, that’s not necessarily the case.

furnace that’s too big for your home will heat your home very quickly then shut off, repeating this process several times throughout the day. This frequent turning on and off (called “short cycling”) wears out your furnace and causes uneven heating throughout your home.

furnace that’s too small for your home will constantly struggle to heat your home to the temperature set on your thermostat. It will run longer to compensate, which leads to increased energy bills and more wear and tear on your furnace.

Since both sizing problems lead to higher energy bills, potential repairs and general discomfort, it’s best to have a furnace professional size your system correctly. That way, you’ll avoid all of those costly and frustrating issues down the road.

Need a furnace recommendation from a Boise pro?

Our comfort specialists are trained to perform load calculations to help you find the right size furnace for your home. With over 30 years of experience, we’ve helped thousands of Boise homeowners with their heating needs.

To learn more about what to expect when you hire us to install your furnace, visit our furnace installation page.

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