485. What is a Heat Loss / Heat Gain?
28 Jan 2026 · 3 min
Derek Cole explains heat loss and heat gain calculations, which determine what size HVAC system a home needs. Changes like new windows, doors, or insulation can shift the load even if an older unit worked fine. Licensed contractors should produce written calculations and may need to show them to state boards.
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I was recently told that when getting a new estimate for a heating and air conditioning unit, I should ask for a heat loss calculation. What is that and is it important?
Hey everyone, I'm Derek Cole, host of the Derek Cole Podcast. And we believe in taking the time to explain how things work for your air at home or your business. Let's get into today's episode. Please listen closely and maybe even take some notes so you can remember these insights of home comfort and energy savings. And share this episode with three of your friends because we all need to share better ways to be more comfortable at home. Be sure to tag me or DM me on Instagram Derek Mcole so I can say hi, thanks again for listening. And let's begin.
I will tell you what separates the companies from each other. The companies that provide a heat loss calculation and the companies that do not. That will tell you pretty quickly who you're dealing with. On every install, we do a heat load calculation, which is a load calculation on your house to make sure that it is the right size unit going into your house. Now, it doesn't matter if you had a 4 ton unit for 25 years in your house because we still need to do one. And because you probably replaced the windows, the doors, add the insulation, replace the roof, got more insulation, something has changed in that space. So we're just going to calculate again what is needed, how much heat loss or heat gain your house has that will allow us to properly size the unit and then we'll put the unit into your home. A company that does not provide this is one that's not doing it. And you probably don't want them doing your home because it really does separate companies, you know, we do want them on every install. If you're a state license holder, you have to do one. If the state board were to come in here and say, hey, so and so, customer said you guys installed a three ton, it should have been a.
Two and a half ton.
Let me see your heat loss, heat gain, and then boom, you gotta show it to them. So you have to do on every install and you should do one. And regardless, you know, I've heard it many, many times. Same unit I've had for 30 years. 20 years, 15 years. I understand, I get it, I understand that. But this step needs to be done just to make sure. I mean, it's going to take another 15, 30 minutes. And this is a 10 year investment at least. So let's make sure we're doing it right the first time.
Okay? I hope you enjoyed this episode of the Derek Cole Podcast. Tell some people about this episode. It's on each of us really to spread the better ways to be healthier and more comfortable in our homes and workspaces. I'm asking you to be the dealer of positive and life changing messages in your circle of influence. Take a screenshot right now and share the screenshot and the link to this episode with three of your friends. To today share on social media use the hashtag Healthy Home. That's Healthy Home. We are always giving away shout outs prizes to our community. If you would like to help me personally then please rate and review on Apple podcast. Give us some stars. Leave a review because that stuff actually does help and I read all the comments. So my last thought for today please remember you deserve better air at home and greater comfort at home. Don't settle for being uncomfortable for your heating air every single month. We are so thankful for having you here in our community and be sure to go deeper with us at simmons1hour.com.
It.
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